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# Source code for torch.nn.modules.module

    from collections import OrderedDict, namedtuple
    import itertools
    import warnings
    import functools
    import weakref

    import torch
    from ..parameter import Parameter
    import torch.utils.hooks as hooks

    from torch import Tensor, device, dtype
    from typing import Union, Tuple, Any, Callable, Iterator, Set, Optional, overload, TypeVar, Mapping, Dict, List
    from ...utils.hooks import RemovableHandle

    __all__ = ['register_module_forward_pre_hook', 'register_module_forward_hook',
               'register_module_full_backward_pre_hook', 'register_module_backward_hook',
               'register_module_full_backward_hook', 'register_module_buffer_registration_hook',
               'register_module_module_registration_hook', 'register_module_parameter_registration_hook', 'Module']

    _grad_t = Union[Tuple[Tensor, ...], Tensor]
    # See https://mypy.readthedocs.io/en/latest/generics.html#generic-methods-and-generic-self for the use
    # of `T` to annotate `self`. Many methods of `Module` return `self` and we want those return values to be
    # the type of the subclass, not the looser type of `Module`.
    T = TypeVar('T', bound='Module')

    class _IncompatibleKeys(namedtuple('IncompatibleKeys', ['missing_keys', 'unexpected_keys'])):
        def __repr__(self):
            if not self.missing_keys and not self.unexpected_keys:
                return '<All keys matched successfully>'
            return super().__repr__()

        __str__ = __repr__

    def _addindent(s_, numSpaces):
        s = s_.split('\n')
        # don't do anything for single-line stuff
        if len(s) == 1:
            return s_
        first = s.pop(0)
        s = [(numSpaces * ' ') + line for line in s]
        s = '\n'.join(s)
        s = first + '\n' + s
        return s

    r"""This tracks hooks common to all modules that are executed immediately before
    .registering the buffer/module/parameter"""
    _global_buffer_registration_hooks: Dict[int, Callable] = OrderedDict()
    _global_module_registration_hooks: Dict[int, Callable] = OrderedDict()
    _global_parameter_registration_hooks: Dict[int, Callable] = OrderedDict()

    class _WrappedHook:
        def __init__(self, hook: Callable, module: Optional["Module"] = None):
            self.hook: Callable = hook
            functools.update_wrapper(self, hook)

            self.with_module: bool = False

            if module is not None:
                self.module: weakref.ReferenceType[Module] = weakref.ref(module)
                self.with_module = True

        def __call__(self, *args: Any, **kwargs: Any) -> Any:
            if self.with_module:
                module = self.module()
                if module is None:
                    raise RuntimeError("You are trying to call the hook of a dead Module!")
                return self.hook(module, *args, **kwargs)
            return self.hook(*args, **kwargs)

        def __getstate__(self) -> Dict:
            result = {"hook": self.hook, "with_module": self.with_module}
            if self.with_module:
                result["module"] = self.module()

            return result

        def __setstate__(self, state: Dict):
            self.hook = state["hook"]
            self.with_module = state["with_module"]

            if self.with_module:
                if state["module"] is None:
                    raise RuntimeError("You are trying to revive the hook of a dead Module!")
                self.module = weakref.ref(state["module"])

    r"""This tracks hooks common to all modules that are executed before/after
    calling forward and backward. This is global state used for debugging/profiling
    purposes"""
    _global_backward_pre_hooks: Dict[int, Callable] = OrderedDict()
    _global_backward_hooks: Dict[int, Callable] = OrderedDict()
    _global_is_full_backward_hook: Optional[bool] = None
    _global_forward_pre_hooks: Dict[int, Callable] = OrderedDict()
    _global_forward_hooks: Dict[int, Callable] = OrderedDict()
    _global_forward_hooks_always_called: Dict[int, bool] = OrderedDict()

    _EXTRA_STATE_KEY_SUFFIX = '_extra_state'

    def register_module_buffer_registration_hook(hook: Callable[..., None]) -> RemovableHandle:
        r"""Registers a buffer registration hook common to all modules.

        .. warning ::

            This adds global state to the `nn.Module` module

        The hook will be called every time :func:`register_buffer` is invoked.
        It should have the following signature::

            hook(module, name, buffer) -> None or new buffer

        The hook can modify the input or return a single modified value in the hook.

        Returns:
            :class:`torch.utils.hooks.RemovableHandle`:
                a handle that can be used to remove the added hook by calling
                ``handle.remove()``
        """
        handle = hooks.RemovableHandle(_global_buffer_registration_hooks)
        _global_buffer_registration_hooks[handle.id] = hook
        return handle

    def register_module_module_registration_hook(hook: Callable[..., None]) -> RemovableHandle:
        r"""Registers a module registration hook common to all modules.

        .. warning ::

            This adds global state to the `nn.Module` module

        The hook will be called every time :func:`register_module` is invoked.
        It should have the following signature::

            hook(module, name, submodule) -> None or new submodule

        The hook can modify the input or return a single modified value in the hook.

        Returns:
            :class:`torch.utils.hooks.RemovableHandle`:
                a handle that can be used to remove the added hook by calling
                ``handle.remove()``
        """
        handle = hooks.RemovableHandle(_global_module_registration_hooks)
        _global_module_registration_hooks[handle.id] = hook
        return handle

    def register_module_parameter_registration_hook(hook: Callable[..., None]) -> RemovableHandle:
        r"""Registers a parameter registration hook common to all modules.

        .. warning ::

            This adds global state to the `nn.Module` module

        The hook will be called every time :func:`register_parameter` is invoked.
        It should have the following signature::

            hook(module, name, param) -> None or new parameter

        The hook can modify the input or return a single modified value in the hook.

        Returns:
            :class:`torch.utils.hooks.RemovableHandle`:
                a handle that can be used to remove the added hook by calling
                ``handle.remove()``
        """
        handle = hooks.RemovableHandle(_global_parameter_registration_hooks)
        _global_parameter_registration_hooks[handle.id] = hook
        return handle

    def register_module_forward_pre_hook(hook: Callable[..., None]) -> RemovableHandle:
        r"""Registers a forward pre-hook common to all modules.

        .. warning ::

            This adds global state to the `nn.module` module
            and it is only intended for debugging/profiling purposes.

        The hook will be called every time before :func:`forward` is invoked.
        It should have the following signature::

            hook(module, input) -> None or modified input

        The input contains only the positional arguments given to the module.
        Keyword arguments won't be passed to the hooks and only to the ``forward``.
        The hook can modify the input. User can either return a tuple or a
        single modified value in the hook. We will wrap the value into a tuple
        if a single value is returned(unless that value is already a tuple).

        This hook has precedence over the specific module hooks registered with
        ``register_forward_pre_hook``.

        Returns:
            :class:`torch.utils.hooks.RemovableHandle`:
                a handle that can be used to remove the added hook by calling
                ``handle.remove()``
        """
        handle = hooks.RemovableHandle(_global_forward_pre_hooks)
        _global_forward_pre_hooks[handle.id] = hook
        return handle

    def register_module_forward_hook(hook: Callable[..., None], *, always_call: bool = False) -> RemovableHandle:
        r"""Registers a global forward hook for all the modules

        .. warning ::

            This adds global state to the `nn.module` module
            and it is only intended for debugging/profiling purposes.

        The hook will be called every time after :func:`forward` has computed an output.
        It should have the following signature::

            hook(module, input, output) -> None or modified output

        The input contains only the positional arguments given to the module.
        Keyword arguments won't be passed to the hooks and only to the ``forward``.
        The hook can modify the output. It can modify the input inplace but
        it will not have effect on forward since this is called after
        :func:`forward` is called.

        Parameters:
            hook (Callable): The user defined hook to be registered.
            always_call (bool): If ``True`` the ``hook`` will be run regardless of
                whether an exception is raised while calling the Module.
                Default: ``False``
        Returns:
            :class:`torch.utils.hooks.RemovableHandle`:
                a handle that can be used to remove the added hook by calling
                ``handle.remove()``

        This hook will be executed before specific module hooks registered with
        ``register_forward_hook``.
        """
        handle = hooks.RemovableHandle(_global_forward_hooks,
                                       extra_dict=_global_forward_hooks_always_called)
        _global_forward_hooks[handle.id] = hook
        if always_call:
            _global_forward_hooks_always_called[handle.id] = True
        return handle

    def register_module_backward_hook(
        hook: Callable[['Module', _grad_t, _grad_t], Union[None, _grad_t]]
    ) -> RemovableHandle:
        r"""Registers a backward hook common to all the modules.

        This function is deprecated in favor of
        :func:`torch.nn.modules.module.register_module_full_backward_hook`
        and the behavior of this function will change in future versions.

        Returns:
            :class:`torch.utils.hooks.RemovableHandle`:
                a handle that can be used to remove the added hook by calling
                ``handle.remove()``

        """
        global _global_is_full_backward_hook
        if _global_is_full_backward_hook is True:
            raise RuntimeError("Cannot use both regular backward hooks and full backward hooks as a "
                               "global Module hook. Please use only one of them.")

        _global_is_full_backward_hook = False

        handle = hooks.RemovableHandle(_global_backward_hooks)
        _global_backward_hooks[handle.id] = hook
        return handle

    def register_module_full_backward_pre_hook(
        hook: Callable[['Module', _grad_t], Union[None, _grad_t]]
    ) -> RemovableHandle:
        r"""Registers a backward pre-hook common to all the modules.

        .. warning ::
            This adds global state to the `nn.module` module
            and it is only intended for debugging/profiling purposes.

        The hook will be called every time the gradients for the module are computed.
        The hook should have the following signature::

            hook(module, grad_output) -> Tensor or None

        The :attr:`grad_output` is a tuple. The hook should
        not modify its arguments, but it can optionally return a new gradient with
        respect to the output that will be used in place of :attr:`grad_output` in
        subsequent computations. Entries in :attr:`grad_output` will be ``None`` for
        all non-Tensor arguments.

        For technical reasons, when this hook is applied to a Module, its forward function will
        receive a view of each Tensor passed to the Module. Similarly the caller will receive a view
        of each Tensor returned by the Module's forward function.

        Global hooks are called before hooks registered with `register_backward_pre_hook`

        Returns:
            :class:`torch.utils.hooks.RemovableHandle`:
                a handle that can be used to remove the added hook by calling
                ``handle.remove()``

        """
        handle = hooks.RemovableHandle(_global_backward_pre_hooks)
        _global_backward_pre_hooks[handle.id] = hook
        return handle

    def register_module_full_backward_hook(
        hook: Callable[['Module', _grad_t, _grad_t], Union[None, _grad_t]]
    ) -> RemovableHandle:
        r"""Registers a backward hook common to all the modules.

        .. warning ::
            This adds global state to the `nn.module` module
            and it is only intended for debugging/profiling purposes.

        The hook will be called every time the gradients with respect to a module
        are computed, i.e. the hook will execute if and only if the gradients with
        respect to module outputs are computed. The hook should have the following
        signature::

            hook(module, grad_input, grad_output) -> Tensor or None

        The :attr:`grad_input` and :attr:`grad_output` are tuples. The hook should
        not modify its arguments, but it can optionally return a new gradient with
        respect to the input that will be used in place of :attr:`grad_input` in
        subsequent computations. :attr:`grad_input` will only correspond to the inputs given
        as positional arguments and all kwarg arguments will not appear in the hook. Entries
        in :attr:`grad_input` and :attr:`grad_output` will be ``None`` for all non-Tensor
        arguments.

        For technical reasons, when this hook is applied to a Module, its forward function will
        receive a view of each Tensor passed to the Module. Similarly the caller will receive a view
        of each Tensor returned by the Module's forward function.

        Global hooks are called before hooks registered with `register_backward_hook`

        Returns:
            :class:`torch.utils.hooks.RemovableHandle`:
                a handle that can be used to remove the added hook by calling
                ``handle.remove()``

        """
        global _global_is_full_backward_hook
        if _global_is_full_backward_hook is False:
            raise RuntimeError("Cannot use both regular backward hooks and full backward hooks as a "
                               "global Module hook. Please use only one of them.")

        _global_is_full_backward_hook = True

        handle = hooks.RemovableHandle(_global_backward_hooks)
        _global_backward_hooks[handle.id] = hook
        return handle

    # Trick mypy into not applying contravariance rules to inputs by defining
    # forward as a value, rather than a function.  See also
    # https://github.com/python/mypy/issues/8795
    def _forward_unimplemented(self, *input: Any) -> None:
        r"""Defines the computation performed at every call.

        Should be overridden by all subclasses.

        .. note::
            Although the recipe for forward pass needs to be defined within
            this function, one should call the :class:`Module` instance afterwards
            instead of this since the former takes care of running the
            registered hooks while the latter silently ignores them.
        """
        raise NotImplementedError(f"Module [{type(self).__name__}] is missing the required \"forward\" function")

    class Module:
        r"""Base class for all neural network modules.

        Your models should also subclass this class.

        Modules can also contain other Modules, allowing to nest them in
        a tree structure. You can assign the submodules as regular attributes::

            import torch.nn as nn
            import torch.nn.functional as F

            class Model(nn.Module):
                def __init__(self):
                    super().__init__()
                    self.conv1 = nn.Conv2d(1, 20, 5)
                    self.conv2 = nn.Conv2d(20, 20, 5)

                def forward(self, x):
                    x = F.relu(self.conv1(x))
                    return F.relu(self.conv2(x))

        Submodules assigned in this way will be registered, and will have their
        parameters converted too when you call :meth:`to`, etc.

        .. note::
            As per the example above, an ``__init__()`` call to the parent class
            must be made before assignment on the child.

        :ivar training: Boolean represents whether this module is in training or
                        evaluation mode.
        :vartype training: bool
        """

        dump_patches: bool = False

        _version: int = 1
        r"""This allows better BC support for :meth:`load_state_dict`. In
        :meth:`state_dict`, the version number will be saved as in the attribute
        `_metadata` of the returned state dict, and thus pickled. `_metadata` is a
        dictionary with keys that follow the naming convention of state dict. See
        ``_load_from_state_dict`` on how to use this information in loading.

        If new parameters/buffers are added/removed from a module, this number shall
        be bumped, and the module's `_load_from_state_dict` method can compare the
        version number and do appropriate changes if the state dict is from before
        the change."""

        training: bool
        _parameters: Dict[str, Optional[Parameter]]
        _buffers: Dict[str, Optional[Tensor]]
        _non_persistent_buffers_set: Set[str]
        _backward_pre_hooks: Dict[int, Callable]
        _backward_hooks: Dict[int, Callable]
        _is_full_backward_hook: Optional[bool]
        _forward_hooks: Dict[int, Callable]
        # Marks whether the corresponding _forward_hooks accept kwargs or not.
        # As JIT does not support Set[int], this dict is used as a set, where all
        # hooks represented in this dict accept kwargs.
        _forward_hooks_with_kwargs: Dict[int, bool]
        # forward hooks that should always be called even if an exception is raised
        _forward_hooks_always_called: Dict[int, bool]
        _forward_pre_hooks: Dict[int, Callable]
        # Marks whether the corresponding _forward_hooks accept kwargs or not.
        # As JIT does not support Set[int], this dict is used as a set, where all
        # hooks represented in this dict accept kwargs.
        _forward_pre_hooks_with_kwargs: Dict[int, bool]
        _state_dict_hooks: Dict[int, Callable]
        _load_state_dict_pre_hooks: Dict[int, Callable]
        _state_dict_pre_hooks: Dict[int, Callable]
        _load_state_dict_post_hooks: Dict[int, Callable]
        _modules: Dict[str, Optional['Module']]
        call_super_init: bool = False
        _compiled_call_impl : Optional[Callable] = None

        def __init__(self, *args, **kwargs) -> None:
            """
            Initializes internal Module state, shared by both nn.Module and ScriptModule.
            """

            torch._C._log_api_usage_once("python.nn_module")

            # Backward compatibility: no args used to be allowed when call_super_init=False
            if self.call_super_init is False and bool(kwargs):
                raise TypeError("{}.__init__() got an unexpected keyword argument '{}'"
                                "".format(type(self).__name__, next(iter(kwargs))))

            if self.call_super_init is False and bool(args):
                raise TypeError(f"{type(self).__name__}.__init__() takes 1 positional argument but {len(args) + 1} were"
                                " given")

            """
            Calls super().__setattr__('a', a) instead of the typical self.a = a
            to avoid Module.__setattr__ overhead. Module's __setattr__ has special
            handling for parameters, submodules, and buffers but simply calls into
            super().__setattr__ for all other attributes.
            """
            super().__setattr__('training', True)
            super().__setattr__('_parameters', OrderedDict())
            super().__setattr__('_buffers', OrderedDict())
            super().__setattr__('_non_persistent_buffers_set', set())
            super().__setattr__('_backward_pre_hooks', OrderedDict())
            super().__setattr__('_backward_hooks', OrderedDict())
            super().__setattr__('_is_full_backward_hook', None)
            super().__setattr__('_forward_hooks', OrderedDict())
            super().__setattr__('_forward_hooks_with_kwargs', OrderedDict())
            super().__setattr__('_forward_hooks_always_called', OrderedDict())
            super().__setattr__('_forward_pre_hooks', OrderedDict())
            super().__setattr__('_forward_pre_hooks_with_kwargs', OrderedDict())
            super().__setattr__('_state_dict_hooks', OrderedDict())
            super().__setattr__('_state_dict_pre_hooks', OrderedDict())
            super().__setattr__('_load_state_dict_pre_hooks', OrderedDict())
            super().__setattr__('_load_state_dict_post_hooks', OrderedDict())
            super().__setattr__('_modules', OrderedDict())

            if self.call_super_init:
                super().__init__(*args, **kwargs)

        forward: Callable[..., Any] = _forward_unimplemented

        def register_buffer(self, name: str, tensor: Optional[Tensor], persistent: bool = True) -> None:
            r"""Adds a buffer to the module.

            This is typically used to register a buffer that should not to be
            considered a model parameter. For example, BatchNorm's ``running_mean``
            is not a parameter, but is part of the module's state. Buffers, by
            default, are persistent and will be saved alongside parameters. This
            behavior can be changed by setting :attr:`persistent` to ``False``. The
            only difference between a persistent buffer and a non-persistent buffer
            is that the latter will not be a part of this module's
            :attr:`state_dict`.

            Buffers can be accessed as attributes using given names.

            Args:
                name (str): name of the buffer. The buffer can be accessed
                    from this module using the given name
                tensor (Tensor or None): buffer to be registered. If ``None``, then operations
                    that run on buffers, such as :attr:`cuda`, are ignored. If ``None``,
                    the buffer is **not** included in the module's :attr:`state_dict`.
                persistent (bool): whether the buffer is part of this module's
                    :attr:`state_dict`.

            Example::

                >>> # xdoctest: +SKIP("undefined vars")
                >>> self.register_buffer('running_mean', torch.zeros(num_features))

            """
            if persistent is False and isinstance(self, torch.jit.ScriptModule):
                raise RuntimeError("ScriptModule does not support non-persistent buffers")

            if '_buffers' not in self.__dict__:
                raise AttributeError(
                    "cannot assign buffer before Module.__init__() call")
            elif not isinstance(name, str):
                raise TypeError(f"buffer name should be a string. Got {torch.typename(name)}")
            elif '.' in name:
                raise KeyError("buffer name can't contain \".\"")
            elif name == '':
                raise KeyError("buffer name can't be empty string \"\"")
            elif hasattr(self, name) and name not in self._buffers:
                raise KeyError(f"attribute '{name}' already exists")
            elif tensor is not None and not isinstance(tensor, torch.Tensor):
                raise TypeError(f"cannot assign '{torch.typename(tensor)}' object to buffer '{name}' "
                                "(torch Tensor or None required)"
                                )
            else:
                for hook in _global_buffer_registration_hooks.values():
                    output = hook(self, name, tensor)
                    if output is not None:
                        tensor = output
                self._buffers[name] = tensor
                if persistent:
                    self._non_persistent_buffers_set.discard(name)
                else:
                    self._non_persistent_buffers_set.add(name)

        def register_parameter(self, name: str, param: Optional[Parameter]) -> None:
            r"""Adds a parameter to the module.

            The parameter can be accessed as an attribute using given name.

            Args:
                name (str): name of the parameter. The parameter can be accessed
                    from this module using the given name
                param (Parameter or None): parameter to be added to the module. If
                    ``None``, then operations that run on parameters, such as :attr:`cuda`,
                    are ignored. If ``None``, the parameter is **not** included in the
                    module's :attr:`state_dict`.
            """
            if '_parameters' not in self.__dict__:
                raise AttributeError(
                    "cannot assign parameter before Module.__init__() call")

            elif not isinstance(name, str):
                raise TypeError(f"parameter name should be a string. Got {torch.typename(name)}")
            elif '.' in name:
                raise KeyError("parameter name can't contain \".\"")
            elif name == '':
                raise KeyError("parameter name can't be empty string \"\"")
            elif hasattr(self, name) and name not in self._parameters:
                raise KeyError(f"attribute '{name}' already exists")

            if param is None:
                self._parameters[name] = None
            elif not isinstance(param, Parameter):
                raise TypeError(f"cannot assign '{torch.typename(param)}' object to parameter '{name}' "
                                "(torch.nn.Parameter or None required)"
                                )
            elif param.grad_fn:
                raise ValueError(
                    f"Cannot assign non-leaf Tensor to parameter '{name}'. Model "
                    f"parameters must be created explicitly. To express '{name}' "
                    "as a function of another Tensor, compute the value in "
                    "the forward() method.")
            else:
                for hook in _global_parameter_registration_hooks.values():
                    output = hook(self, name, param)
                    if output is not None:
                        param = output
                self._parameters[name] = param

        def add_module(self, name: str, module: Optional['Module']) -> None:
            r"""Adds a child module to the current module.

            The module can be accessed as an attribute using the given name.

            Args:
                name (str): name of the child module. The child module can be
                    accessed from this module using the given name
                module (Module): child module to be added to the module.
            """
            if not isinstance(module, Module) and module is not None:
                raise TypeError(f"{torch.typename(module)} is not a Module subclass")
            elif not isinstance(name, str):
                raise TypeError(f"module name should be a string. Got {torch.typename(name)}")
            elif hasattr(self, name) and name not in self._modules:
                raise KeyError(f"attribute '{name}' already exists")
            elif '.' in name:
                raise KeyError(f"module name can't contain \".\", got: {name}")
            elif name == '':
                raise KeyError("module name can't be empty string \"\"")
            for hook in _global_module_registration_hooks.values():
                output = hook(self, name, module)
                if output is not None:
                    module = output
            self._modules[name] = module

        def register_module(self, name: str, module: Optional['Module']) -> None:
            r"""Alias for :func:`add_module`."""
            self.add_module(name, module)

        def get_submodule(self, target: str) -> "Module":
            """
            Returns the submodule given by ``target`` if it exists,
            otherwise throws an error.

            For example, let's say you have an ``nn.Module`` ``A`` that
            looks like this:

            .. code-block:: text

                A(
                    (net_b): Module(
                        (net_c): Module(
                            (conv): Conv2d(16, 33, kernel_size=(3, 3), stride=(2, 2))
                        )
                        (linear): Linear(in_features=100, out_features=200, bias=True)
                    )
                )

            (The diagram shows an ``nn.Module`` ``A``. ``A`` has a nested
            submodule ``net_b``, which itself has two submodules ``net_c``
            and ``linear``. ``net_c`` then has a submodule ``conv``.)

            To check whether or not we have the ``linear`` submodule, we
            would call ``get_submodule("net_b.linear")``. To check whether
            we have the ``conv`` submodule, we would call
            ``get_submodule("net_b.net_c.conv")``.

            The runtime of ``get_submodule`` is bounded by the degree
            of module nesting in ``target``. A query against
            ``named_modules`` achieves the same result, but it is O(N) in
            the number of transitive modules. So, for a simple check to see
            if some submodule exists, ``get_submodule`` should always be
            used.

            Args:
                target: The fully-qualified string name of the submodule
                    to look for. (See above example for how to specify a
                    fully-qualified string.)

            Returns:
                torch.nn.Module: The submodule referenced by ``target``

            Raises:
                AttributeError: If the target string references an invalid
                    path or resolves to something that is not an
                    ``nn.Module``
            """
            if target == "":
                return self

            atoms: List[str] = target.split(".")
            mod: torch.nn.Module = self

            for item in atoms:

                if not hasattr(mod, item):
                    raise AttributeError(mod._get_name() + " has no "
                                         "attribute `" + item + "`")

                mod = getattr(mod, item)

                if not isinstance(mod, torch.nn.Module):
                    raise AttributeError("`" + item + "` is not "
                                         "an nn.Module")

            return mod

        def get_parameter(self, target: str) -> "Parameter":
            """
            Returns the parameter given by ``target`` if it exists,
            otherwise throws an error.

            See the docstring for ``get_submodule`` for a more detailed
            explanation of this method's functionality as well as how to
            correctly specify ``target``.

            Args:
                target: The fully-qualified string name of the Parameter
                    to look for. (See ``get_submodule`` for how to specify a
                    fully-qualified string.)

            Returns:
                torch.nn.Parameter: The Parameter referenced by ``target``

            Raises:
                AttributeError: If the target string references an invalid
                    path or resolves to something that is not an
                    ``nn.Parameter``
            """
            module_path, _, param_name = target.rpartition(".")

            mod: torch.nn.Module = self.get_submodule(module_path)

            if not hasattr(mod, param_name):
                raise AttributeError(mod._get_name() + " has no attribute `"
                                     + param_name + "`")

            param: torch.nn.Parameter = getattr(mod, param_name)

            if not isinstance(param, torch.nn.Parameter):
                raise AttributeError("`" + param_name + "` is not an "
                                     "nn.Parameter")

            return param

        def get_buffer(self, target: str) -> "Tensor":
            """
            Returns the buffer given by ``target`` if it exists,
            otherwise throws an error.

            See the docstring for ``get_submodule`` for a more detailed
            explanation of this method's functionality as well as how to
            correctly specify ``target``.

            Args:
                target: The fully-qualified string name of the buffer
                    to look for. (See ``get_submodule`` for how to specify a
                    fully-qualified string.)

            Returns:
                torch.Tensor: The buffer referenced by ``target``

            Raises:
                AttributeError: If the target string references an invalid
                    path or resolves to something that is not a
                    buffer
            """
            module_path, _, buffer_name = target.rpartition(".")

            mod: torch.nn.Module = self.get_submodule(module_path)

            if not hasattr(mod, buffer_name):
                raise AttributeError(mod._get_name() + " has no attribute `"
                                     + buffer_name + "`")

            buffer: torch.Tensor = getattr(mod, buffer_name)

            if buffer_name not in mod._buffers:
                raise AttributeError("`" + buffer_name + "` is not a buffer")

            return buffer

        def get_extra_state(self) -> Any:
            """
            Returns any extra state to include in the module's state_dict.
            Implement this and a corresponding :func:`set_extra_state` for your module
            if you need to store extra state. This function is called when building the
            module's `state_dict()`.

            Note that extra state should be picklable to ensure working serialization
            of the state_dict. We only provide provide backwards compatibility guarantees
            for serializing Tensors; other objects may break backwards compatibility if
            their serialized pickled form changes.

            Returns:
                object: Any extra state to store in the module's state_dict
            """
            raise RuntimeError(
                "Reached a code path in Module.get_extra_state() that should never be called. "
                "Please file an issue at https://github.com/pytorch/pytorch/issues/new?template=bug-report.yml "
                "to report this bug.")

        def set_extra_state(self, state: Any):
            """
            This function is called from :func:`load_state_dict` to handle any extra state
            found within the `state_dict`. Implement this function and a corresponding
            :func:`get_extra_state` for your module if you need to store extra state within its
            `state_dict`.

            Args:
                state (dict): Extra state from the `state_dict`
            """
            raise RuntimeError(
                "Reached a code path in Module.set_extra_state() that should never be called. "
                "Please file an issue at https://github.com/pytorch/pytorch/issues/new?template=bug-report.yml "
                "to report this bug.")

        def _apply(self, fn, recurse=True):
            if recurse:
                for module in self.children():
                    module._apply(fn)

            def compute_should_use_set_data(tensor, tensor_applied):
                if torch._has_compatible_shallow_copy_type(tensor, tensor_applied):
                    # If the new tensor has compatible tensor type as the existing tensor,
                    # the current behavior is to change the tensor in-place using `.data =`,
                    # and the future behavior is to overwrite the existing tensor. However,
                    # changing the current behavior is a BC-breaking change, and we want it
                    # to happen in future releases. So for now we introduce the
                    # `torch.__future__.get_overwrite_module_params_on_conversion()`
                    # global flag to let the user control whether they want the future
                    # behavior of overwriting the existing tensor or not.
                    return not torch.__future__.get_overwrite_module_params_on_conversion()
                else:
                    return False

            for key, param in self._parameters.items():
                if param is None:
                    continue
                # Tensors stored in modules are graph leaves, and we don't want to
                # track autograd history of `param_applied`, so we have to use
                # `with torch.no_grad():`
                with torch.no_grad():
                    param_applied = fn(param)
                should_use_set_data = compute_should_use_set_data(param, param_applied)
                if should_use_set_data:
                    param.data = param_applied
                    out_param = param
                else:
                    assert isinstance(param, Parameter)
                    assert param.is_leaf
                    out_param = Parameter(param_applied, param.requires_grad)
                    self._parameters[key] = out_param

                if param.grad is not None:
                    with torch.no_grad():
                        grad_applied = fn(param.grad)
                    should_use_set_data = compute_should_use_set_data(param.grad, grad_applied)
                    if should_use_set_data:
                        assert out_param.grad is not None
                        out_param.grad.data = grad_applied
                    else:
                        assert param.grad.is_leaf
                        out_param.grad = grad_applied.requires_grad_(param.grad.requires_grad)

            for key, buf in self._buffers.items():
                if buf is not None:
                    self._buffers[key] = fn(buf)

            return self

        def apply(self: T, fn: Callable[['Module'], None]) -> T:
            r"""Applies ``fn`` recursively to every submodule (as returned by ``.children()``)
            as well as self. Typical use includes initializing the parameters of a model
            (see also :ref:`nn-init-doc`).

            Args:
                fn (:class:`Module` -> None): function to be applied to each submodule

            Returns:
                Module: self

            Example::

                >>> @torch.no_grad()
                >>> def init_weights(m):
                >>>     print(m)
                >>>     if type(m) == nn.Linear:
                >>>         m.weight.fill_(1.0)
                >>>         print(m.weight)
                >>> net = nn.Sequential(nn.Linear(2, 2), nn.Linear(2, 2))
                >>> net.apply(init_weights)
                Linear(in_features=2, out_features=2, bias=True)
                Parameter containing:
                tensor([[1., 1.],
                        [1., 1.]], requires_grad=True)
                Linear(in_features=2, out_features=2, bias=True)
                Parameter containing:
                tensor([[1., 1.],
                        [1., 1.]], requires_grad=True)
                Sequential(
                  (0): Linear(in_features=2, out_features=2, bias=True)
                  (1): Linear(in_features=2, out_features=2, bias=True)
                )

            """
            for module in self.children():
                module.apply(fn)
            fn(self)
            return self

        def cuda(self: T, device: Optional[Union[int, device]] = None) -> T:
            r"""Moves all model parameters and buffers to the GPU.

            This also makes associated parameters and buffers different objects. So
            it should be called before constructing optimizer if the module will
            live on GPU while being optimized.

            .. note::
                This method modifies the module in-place.

            Args:
                device (int, optional): if specified, all parameters will be
                    copied to that device

            Returns:
                Module: self
            """
            return self._apply(lambda t: t.cuda(device))

        def ipu(self: T, device: Optional[Union[int, device]] = None) -> T:
            r"""Moves all model parameters and buffers to the IPU.

            This also makes associated parameters and buffers different objects. So
            it should be called before constructing optimizer if the module will
            live on IPU while being optimized.

            .. note::
                This method modifies the module in-place.

            Arguments:
                device (int, optional): if specified, all parameters will be
                    copied to that device

            Returns:
                Module: self
            """
            return self._apply(lambda t: t.ipu(device))

        def xpu(self: T, device: Optional[Union[int, device]] = None) -> T:
            r"""Moves all model parameters and buffers to the XPU.

            This also makes associated parameters and buffers different objects. So
            it should be called before constructing optimizer if the module will
            live on XPU while being optimized.

            .. note::
                This method modifies the module in-place.

            Arguments:
                device (int, optional): if specified, all parameters will be
                    copied to that device

            Returns:
                Module: self
            """
            return self._apply(lambda t: t.xpu(device))

        def cpu(self: T) -> T:
            r"""Moves all model parameters and buffers to the CPU.

            .. note::
                This method modifies the module in-place.

            Returns:
                Module: self
            """
            return self._apply(lambda t: t.cpu())

        def type(self: T, dst_type: Union[dtype, str]) -> T:
            r"""Casts all parameters and buffers to :attr:`dst_type`.

            .. note::
                This method modifies the module in-place.

            Args:
                dst_type (type or string): the desired type

            Returns:
                Module: self
            """
            return self._apply(lambda t: t.type(dst_type))

        def float(self: T) -> T:
            r"""Casts all floating point parameters and buffers to ``float`` datatype.

            .. note::
                This method modifies the module in-place.

            Returns:
                Module: self
            """
            return self._apply(lambda t: t.float() if t.is_floating_point() else t)

        def double(self: T) -> T:
            r"""Casts all floating point parameters and buffers to ``double`` datatype.

            .. note::
                This method modifies the module in-place.

            Returns:
                Module: self
            """
            return self._apply(lambda t: t.double() if t.is_floating_point() else t)

        def half(self: T) -> T:
            r"""Casts all floating point parameters and buffers to ``half`` datatype.

            .. note::
                This method modifies the module in-place.

            Returns:
                Module: self
            """
            return self._apply(lambda t: t.half() if t.is_floating_point() else t)

        def bfloat16(self: T) -> T:
            r"""Casts all floating point parameters and buffers to ``bfloat16`` datatype.

            .. note::
                This method modifies the module in-place.

            Returns:
                Module: self
            """
            return self._apply(lambda t: t.bfloat16() if t.is_floating_point() else t)

        def to_empty(self: T, *, device: Union[str, device], recurse: bool = True) -> T:
            r"""Moves the parameters and buffers to the specified device without copying storage.

            Args:
                device (:class:`torch.device`): The desired device of the parameters
                    and buffers in this module.
                recurse (bool): Whether parameters and buffers of submodules should
                    be recursively moved to the specified device.

            Returns:
                Module: self
            """
            return self._apply(lambda t: torch.empty_like(t, device=device), recurse=recurse)

        @overload
        def to(self: T, device: Optional[Union[int, device]] = ..., dtype: Optional[Union[dtype, str]] = ...,
               non_blocking: bool = ...) -> T:
            ...

        @overload
        def to(self: T, dtype: Union[dtype, str], non_blocking: bool = ...) -> T:
            ...

        @overload
        def to(self: T, tensor: Tensor, non_blocking: bool = ...) -> T:
            ...

        def to(self, *args, **kwargs):
            r"""Moves and/or casts the parameters and buffers.

            This can be called as

            .. function:: to(device=None, dtype=None, non_blocking=False)
               :noindex:

            .. function:: to(dtype, non_blocking=False)
               :noindex:

            .. function:: to(tensor, non_blocking=False)
               :noindex:

            .. function:: to(memory_format=torch.channels_last)
               :noindex:

            Its signature is similar to :meth:`torch.Tensor.to`, but only accepts
            floating point or complex :attr:`dtype`\ s. In addition, this method will
            only cast the floating point or complex parameters and buffers to :attr:`dtype`
            (if given). The integral parameters and buffers will be moved
            :attr:`device`, if that is given, but with dtypes unchanged. When
            :attr:`non_blocking` is set, it tries to convert/move asynchronously
            with respect to the host if possible, e.g., moving CPU Tensors with
            pinned memory to CUDA devices.

            See below for examples.

            .. note::
                This method modifies the module in-place.

            Args:
                device (:class:`torch.device`): the desired device of the parameters
                    and buffers in this module
                dtype (:class:`torch.dtype`): the desired floating point or complex dtype of
                    the parameters and buffers in this module
                tensor (torch.Tensor): Tensor whose dtype and device are the desired
                    dtype and device for all parameters and buffers in this module
                memory_format (:class:`torch.memory_format`): the desired memory
                    format for 4D parameters and buffers in this module (keyword
                    only argument)

            Returns:
                Module: self

            Examples::

                >>> # xdoctest: +IGNORE_WANT("non-deterministic")
                >>> linear = nn.Linear(2, 2)
                >>> linear.weight
                Parameter containing:
                tensor([[ 0.1913, -0.3420],
                        [-0.5113, -0.2325]])
                >>> linear.to(torch.double)
                Linear(in_features=2, out_features=2, bias=True)
                >>> linear.weight
                Parameter containing:
                tensor([[ 0.1913, -0.3420],
                        [-0.5113, -0.2325]], dtype=torch.float64)
                >>> # xdoctest: +REQUIRES(env:TORCH_DOCTEST_CUDA1)
                >>> gpu1 = torch.device("cuda:1")
                >>> linear.to(gpu1, dtype=torch.half, non_blocking=True)
                Linear(in_features=2, out_features=2, bias=True)
                >>> linear.weight
                Parameter containing:
                tensor([[ 0.1914, -0.3420],
                        [-0.5112, -0.2324]], dtype=torch.float16, device='cuda:1')
                >>> cpu = torch.device("cpu")
                >>> linear.to(cpu)
                Linear(in_features=2, out_features=2, bias=True)
                >>> linear.weight
                Parameter containing:
                tensor([[ 0.1914, -0.3420],
                        [-0.5112, -0.2324]], dtype=torch.float16)

                >>> linear = nn.Linear(2, 2, bias=None).to(torch.cdouble)
                >>> linear.weight
                Parameter containing:
                tensor([[ 0.3741+0.j,  0.2382+0.j],
                        [ 0.5593+0.j, -0.4443+0.j]], dtype=torch.complex128)
                >>> linear(torch.ones(3, 2, dtype=torch.cdouble))
                tensor([[0.6122+0.j, 0.1150+0.j],
                        [0.6122+0.j, 0.1150+0.j],
                        [0.6122+0.j, 0.1150+0.j]], dtype=torch.complex128)

            """

            device, dtype, non_blocking, convert_to_format = torch._C._nn._parse_to(*args, **kwargs)

            if dtype is not None:
                if not (dtype.is_floating_point or dtype.is_complex):
                    raise TypeError('nn.Module.to only accepts floating point or complex '
                                    f'dtypes, but got desired dtype={dtype}')
                if dtype.is_complex:
                    warnings.warn(
                        "Complex modules are a new feature under active development whose design may change, "
                        "and some modules might not work as expected when using complex tensors as parameters or buffers. "
                        "Please file an issue at https://github.com/pytorch/pytorch/issues/new?template=bug-report.yml "
                        "if a complex module does not work as expected.")

            def convert(t):
                if convert_to_format is not None and t.dim() in (4, 5):
                    return t.to(device, dtype if t.is_floating_point() or t.is_complex() else None,
                                non_blocking, memory_format=convert_to_format)
                return t.to(device, dtype if t.is_floating_point() or t.is_complex() else None, non_blocking)

            return self._apply(convert)

        def register_full_backward_pre_hook(
            self,
            hook: Callable[["Module", _grad_t], Union[None, _grad_t]],
            prepend: bool = False,
        ) -> RemovableHandle:
            r"""Registers a backward pre-hook on the module.

            The hook will be called every time the gradients for the module are computed.
            The hook should have the following signature::

                hook(module, grad_output) -> tuple[Tensor] or None

            The :attr:`grad_output` is a tuple. The hook should
            not modify its arguments, but it can optionally return a new gradient with
            respect to the output that will be used in place of :attr:`grad_output` in
            subsequent computations. Entries in :attr:`grad_output` will be ``None`` for
            all non-Tensor arguments.

            For technical reasons, when this hook is applied to a Module, its forward function will
            receive a view of each Tensor passed to the Module. Similarly the caller will receive a view
            of each Tensor returned by the Module's forward function.

            .. warning ::
                Modifying inputs inplace is not allowed when using backward hooks and
                will raise an error.

            Args:
                hook (Callable): The user-defined hook to be registered.
                prepend (bool): If true, the provided ``hook`` will be fired before
                    all existing ``backward_pre`` hooks on this
                    :class:`torch.nn.modules.Module`. Otherwise, the provided
                    ``hook`` will be fired after all existing ``backward_pre`` hooks
                    on this :class:`torch.nn.modules.Module`. Note that global
                    ``backward_pre`` hooks registered with
                    :func:`register_module_full_backward_pre_hook` will fire before
                    all hooks registered by this method.

            Returns:
                :class:`torch.utils.hooks.RemovableHandle`:
                    a handle that can be used to remove the added hook by calling
                    ``handle.remove()``

            """
            handle = hooks.RemovableHandle(self._backward_pre_hooks)
            self._backward_pre_hooks[handle.id] = hook
            if prepend:
                self._backward_pre_hooks.move_to_end(handle.id, last=False)  # type: ignore[attr-defined]
            return handle

        def register_backward_hook(
            self, hook: Callable[['Module', _grad_t, _grad_t], Union[None, _grad_t]]
        ) -> RemovableHandle:
            r"""Registers a backward hook on the module.

            This function is deprecated in favor of :meth:`~torch.nn.Module.register_full_backward_hook` and
            the behavior of this function will change in future versions.

            Returns:
                :class:`torch.utils.hooks.RemovableHandle`:
                    a handle that can be used to remove the added hook by calling
                    ``handle.remove()``

            """
            if self._is_full_backward_hook is True:
                raise RuntimeError("Cannot use both regular backward hooks and full backward hooks on a "
                                   "single Module. Please use only one of them.")

            self._is_full_backward_hook = False

            handle = hooks.RemovableHandle(self._backward_hooks)
            self._backward_hooks[handle.id] = hook
            return handle

        def register_full_backward_hook(
            self,
            hook: Callable[["Module", _grad_t, _grad_t], Union[None, _grad_t]],
            prepend: bool = False,
        ) -> RemovableHandle:
            r"""Registers a backward hook on the module.

            The hook will be called every time the gradients with respect to a module
            are computed, i.e. the hook will execute if and only if the gradients with
            respect to module outputs are computed. The hook should have the following
            signature::

                hook(module, grad_input, grad_output) -> tuple(Tensor) or None

            The :attr:`grad_input` and :attr:`grad_output` are tuples that contain the gradients
            with respect to the inputs and outputs respectively. The hook should
            not modify its arguments, but it can optionally return a new gradient with
            respect to the input that will be used in place of :attr:`grad_input` in
            subsequent computations. :attr:`grad_input` will only correspond to the inputs given
            as positional arguments and all kwarg arguments are ignored. Entries
            in :attr:`grad_input` and :attr:`grad_output` will be ``None`` for all non-Tensor
            arguments.

            For technical reasons, when this hook is applied to a Module, its forward function will
            receive a view of each Tensor passed to the Module. Similarly the caller will receive a view
            of each Tensor returned by the Module's forward function.

            .. warning ::
                Modifying inputs or outputs inplace is not allowed when using backward hooks and
                will raise an error.

            Args:
                hook (Callable): The user-defined hook to be registered.
                prepend (bool): If true, the provided ``hook`` will be fired before
                    all existing ``backward`` hooks on this
                    :class:`torch.nn.modules.Module`. Otherwise, the provided
                    ``hook`` will be fired after all existing ``backward`` hooks on
                    this :class:`torch.nn.modules.Module`. Note that global
                    ``backward`` hooks registered with
                    :func:`register_module_full_backward_hook` will fire before
                    all hooks registered by this method.

            Returns:
                :class:`torch.utils.hooks.RemovableHandle`:
                    a handle that can be used to remove the added hook by calling
                    ``handle.remove()``

            """
            if self._is_full_backward_hook is False:
                raise RuntimeError("Cannot use both regular backward hooks and full backward hooks on a "
                                   "single Module. Please use only one of them.")

            self._is_full_backward_hook = True

            handle = hooks.RemovableHandle(self._backward_hooks)
            self._backward_hooks[handle.id] = hook
            if prepend:
                self._backward_hooks.move_to_end(handle.id, last=False)  # type: ignore[attr-defined]
            return handle

        def _get_backward_hooks(self):
            r"""Returns the backward hooks for use in the call function.
            It returns two lists, one with the full backward hooks and one with the non-full
            backward hooks.
            """
            full_backward_hooks: List[Callable] = []
            if (_global_is_full_backward_hook is True):
                full_backward_hooks += _global_backward_hooks.values()
            if (self._is_full_backward_hook is True):
                full_backward_hooks += self._backward_hooks.values()

            non_full_backward_hooks: List[Callable] = []
            if (_global_is_full_backward_hook is False):
                non_full_backward_hooks += _global_backward_hooks.values()
            if (self._is_full_backward_hook is False):
                non_full_backward_hooks += self._backward_hooks.values()

            return full_backward_hooks, non_full_backward_hooks

        def _get_backward_pre_hooks(self):
            backward_pre_hooks: List[Callable] = []
            backward_pre_hooks += _global_backward_pre_hooks.values()
            backward_pre_hooks += self._backward_pre_hooks.values()

            return backward_pre_hooks

        def _maybe_warn_non_full_backward_hook(self, inputs, result, grad_fn):
            if not isinstance(result, torch.Tensor):
                if not (isinstance(result, tuple) and all(isinstance(r, torch.Tensor) for r in result)):
                    warnings.warn("Using non-full backward hooks on a Module that does not return a "
                                  "single Tensor or a tuple of Tensors is deprecated and will be removed "
                                  "in future versions. This hook will be missing some of the grad_output. "
                                  "Please use register_full_backward_hook to get the documented behavior.")
                    return
            else:
                result = (result,)

            if not isinstance(inputs, torch.Tensor):
                if not (isinstance(inputs, tuple) and all(isinstance(i, torch.Tensor) for i in inputs)):
                    warnings.warn("Using non-full backward hooks on a Module that does not take as input a "
                                  "single Tensor or a tuple of Tensors is deprecated and will be removed "
                                  "in future versions. This hook will be missing some of the grad_input. "
                                  "Please use register_full_backward_hook to get the documented behavior.")
                    return
            else:
                inputs = (inputs,)

            # At this point we are sure that inputs and result are tuple of Tensors
            out_grad_fn = {r.grad_fn for r in result if r.grad_fn is not None}
            if len(out_grad_fn) == 0 or (len(out_grad_fn) == 1 and grad_fn not in out_grad_fn):
                warnings.warn("Using a non-full backward hook when outputs are nested in python data structure "
                              "is deprecated and will be removed in future versions. This hook will be missing "
                              "some grad_output.")
            elif len(out_grad_fn) > 1:
                warnings.warn("Using a non-full backward hook when outputs are generated by different autograd Nodes "
                              "is deprecated and will be removed in future versions. This hook will be missing "
                              "some grad_output. Please use register_full_backward_hook to get the documented behavior.")
            else:
                # At this point the grad_output part of the hook will most likely be correct
                inputs_grad_fn = {i.grad_fn for i in inputs if i.grad_fn is not None}

                next_functions = {n[0] for n in grad_fn.next_functions}

                if inputs_grad_fn != next_functions:
                    warnings.warn("Using a non-full backward hook when the forward contains multiple autograd Nodes "
                                  "is deprecated and will be removed in future versions. This hook will be missing "
                                  "some grad_input. Please use register_full_backward_hook to get the documented "
                                  "behavior.")

        def register_forward_pre_hook(
            self,
            hook: Union[
                Callable[[T, Tuple[Any, ...]], Optional[Any]],
                Callable[[T, Tuple[Any, ...], Dict[str, Any]], Optional[Tuple[Any, Dict[str, Any]]]],
            ],
            *,
            prepend: bool = False,
            with_kwargs: bool = False,
        ) -> RemovableHandle:
            r"""Registers a forward pre-hook on the module.

            The hook will be called every time before :func:`forward` is invoked.

            If ``with_kwargs`` is false or not specified, the input contains only
            the positional arguments given to the module. Keyword arguments won't be
            passed to the hooks and only to the ``forward``. The hook can modify the
            input. User can either return a tuple or a single modified value in the
            hook. We will wrap the value into a tuple if a single value is returned
            (unless that value is already a tuple). The hook should have the
            following signature::

                hook(module, args) -> None or modified input

            If ``with_kwargs`` is true, the forward pre-hook will be passed the
            kwargs given to the forward function. And if the hook modifies the
            input, both the args and kwargs should be returned. The hook should have
            the following signature::

                hook(module, args, kwargs) -> None or a tuple of modified input and kwargs

            Args:
                hook (Callable): The user defined hook to be registered.
                prepend (bool): If true, the provided ``hook`` will be fired before
                    all existing ``forward_pre`` hooks on this
                    :class:`torch.nn.modules.Module`. Otherwise, the provided
                    ``hook`` will be fired after all existing ``forward_pre`` hooks
                    on this :class:`torch.nn.modules.Module`. Note that global
                    ``forward_pre`` hooks registered with
                    :func:`register_module_forward_pre_hook` will fire before all
                    hooks registered by this method.
                    Default: ``False``
                with_kwargs (bool): If true, the ``hook`` will be passed the kwargs
                    given to the forward function.
                    Default: ``False``

            Returns:
                :class:`torch.utils.hooks.RemovableHandle`:
                    a handle that can be used to remove the added hook by calling
                    ``handle.remove()``
            """
            handle = hooks.RemovableHandle(
                self._forward_pre_hooks,
                extra_dict=self._forward_pre_hooks_with_kwargs
            )
            self._forward_pre_hooks[handle.id] = hook
            if with_kwargs:
                self._forward_pre_hooks_with_kwargs[handle.id] = True

            if prepend:
                self._forward_pre_hooks.move_to_end(handle.id, last=False)  # type: ignore[attr-defined]
            return handle

        def register_forward_hook(
            self,
            hook: Union[
                Callable[[T, Tuple[Any, ...], Any], Optional[Any]],
                Callable[[T, Tuple[Any, ...], Dict[str, Any], Any], Optional[Any]],
            ],
            *,
            prepend: bool = False,
            with_kwargs: bool = False,
            always_call: bool = False,
        ) -> RemovableHandle:
            r"""Registers a forward hook on the module.

            The hook will be called every time after :func:`forward` has computed an output.

            If ``with_kwargs`` is ``False`` or not specified, the input contains only
            the positional arguments given to the module. Keyword arguments won't be
            passed to the hooks and only to the ``forward``. The hook can modify the
            output. It can modify the input inplace but it will not have effect on
            forward since this is called after :func:`forward` is called. The hook
            should have the following signature::

                hook(module, args, output) -> None or modified output

            If ``with_kwargs`` is ``True``, the forward hook will be passed the
            ``kwargs`` given to the forward function and be expected to return the
            output possibly modified. The hook should have the following signature::

                hook(module, args, kwargs, output) -> None or modified output

            Args:
                hook (Callable): The user defined hook to be registered.
                prepend (bool): If ``True``, the provided ``hook`` will be fired
                    before all existing ``forward`` hooks on this
                    :class:`torch.nn.modules.Module`. Otherwise, the provided
                    ``hook`` will be fired after all existing ``forward`` hooks on
                    this :class:`torch.nn.modules.Module`. Note that global
                    ``forward`` hooks registered with
                    :func:`register_module_forward_hook` will fire before all hooks
                    registered by this method.
                    Default: ``False``
                with_kwargs (bool): If ``True``, the ``hook`` will be passed the
                    kwargs given to the forward function.
                    Default: ``False``
                always_call (bool): If ``True`` the ``hook`` will be run regardless of
                    whether an exception is raised while calling the Module.
                    Default: ``False``

            Returns:
                :class:`torch.utils.hooks.RemovableHandle`:
                    a handle that can be used to remove the added hook by calling
                    ``handle.remove()``
            """
            handle = hooks.RemovableHandle(
                self._forward_hooks,
                extra_dict=[self._forward_hooks_with_kwargs, self._forward_hooks_always_called],
            )
            self._forward_hooks[handle.id] = hook
            if with_kwargs:
                self._forward_hooks_with_kwargs[handle.id] = True
            if always_call:
                self._forward_hooks_always_called[handle.id] = True
            if prepend:
                self._forward_hooks.move_to_end(handle.id, last=False)  # type: ignore[attr-defined]
            return handle

        def _slow_forward(self, *input, **kwargs):
            tracing_state = torch._C._get_tracing_state()
            if not tracing_state or isinstance(self.forward, torch._C.ScriptMethod):
                return self.forward(*input, **kwargs)
            recording_scopes = torch.jit._trace._trace_module_map is not None
            if recording_scopes:
                # type ignore was added because at this point one knows that
                # torch.jit._trace._trace_module_map is not Optional and has type Dict[Any, Any]
                name = torch.jit._trace._trace_module_map[self] if self in torch.jit._trace._trace_module_map else None  # type: ignore[index, operator] # noqa: B950
                if name:
                    tracing_state.push_scope(name)
                else:
                    recording_scopes = False
            try:
                result = self.forward(*input, **kwargs)
            finally:
                if recording_scopes:
                    tracing_state.pop_scope()
            return result

        def _wrapped_call_impl(self, *args, **kwargs):
            if self._compiled_call_impl is not None:
                return self._compiled_call_impl(*args, **kwargs)  # type: ignore[misc]
            else:
                return self._call_impl(*args, **kwargs)

        def _call_impl(self, *args, **kwargs):
            forward_call = (self._slow_forward if torch._C._get_tracing_state() else self.forward)
            # If we don't have any hooks, we want to skip the rest of the logic in
            # this function, and just call forward.
            if not (self._backward_hooks or self._backward_pre_hooks or self._forward_hooks or self._forward_pre_hooks
                    or _global_backward_pre_hooks or _global_backward_hooks
                    or _global_forward_hooks or _global_forward_pre_hooks):
                return forward_call(*args, **kwargs)

            try:
                result = None
                called_always_called_hooks = set()

                full_backward_hooks, non_full_backward_hooks = [], []
                backward_pre_hooks = []
                if self._backward_pre_hooks or _global_backward_pre_hooks:
                    backward_pre_hooks = self._get_backward_pre_hooks()

                if self._backward_hooks or _global_backward_hooks:
                    full_backward_hooks, non_full_backward_hooks = self._get_backward_hooks()

                if _global_forward_pre_hooks or self._forward_pre_hooks:
                    for hook_id, hook in (
                        *_global_forward_pre_hooks.items(),
                        *self._forward_pre_hooks.items(),
                    ):
                        if hook_id in self._forward_pre_hooks_with_kwargs:
                            args_kwargs_result = hook(self, args, kwargs)  # type: ignore[misc]
                            if args_kwargs_result is not None:
                                if isinstance(args_kwargs_result, tuple) and len(args_kwargs_result) == 2:
                                    args, kwargs = args_kwargs_result
                                else:
                                    raise RuntimeError(
                                        "forward pre-hook must return None or a tuple "
                                        f"of (new_args, new_kwargs), but got {args_kwargs_result}."
                                    )
                        else:
                            args_result = hook(self, args)
                            if args_result is not None:
                                if not isinstance(args_result, tuple):
                                    args_result = (args_result,)
                                args = args_result

                bw_hook = None
                if full_backward_hooks or backward_pre_hooks:
                    bw_hook = hooks.BackwardHook(self, full_backward_hooks, backward_pre_hooks)
                    args = bw_hook.setup_input_hook(args)

                result = forward_call(*args, **kwargs)
                if _global_forward_hooks or self._forward_hooks:
                    for hook_id, hook in (
                        *_global_forward_hooks.items(),
                        *self._forward_hooks.items(),
                    ):
                        # mark that always called hook is run
                        if hook_id in self._forward_hooks_always_called or hook_id in _global_forward_hooks_always_called:
                            called_always_called_hooks.add(hook_id)

                        if hook_id in self._forward_hooks_with_kwargs:
                            hook_result = hook(self, args, kwargs, result)
                        else:
                            hook_result = hook(self, args, result)

                        if hook_result is not None:
                            result = hook_result

                if bw_hook:
                    if not isinstance(result, (torch.Tensor, tuple)):
                        warnings.warn("For backward hooks to be called,"
                                      " module output should be a Tensor or a tuple of Tensors"
                                      f" but received {type(result)}")
                    result = bw_hook.setup_output_hook(result)

                # Handle the non-full backward hooks
                if non_full_backward_hooks:
                    var = result
                    while not isinstance(var, torch.Tensor):
                        if isinstance(var, dict):
                            var = next(v for v in var.values() if isinstance(v, torch.Tensor))
                        else:
                            var = var[0]
                    grad_fn = var.grad_fn
                    if grad_fn is not None:
                        for hook in non_full_backward_hooks:
                            grad_fn.register_hook(_WrappedHook(hook, self))
                        self._maybe_warn_non_full_backward_hook(args, result, grad_fn)

                return result

            except Exception:
                # run always called hooks if they have not already been run
                # For now only forward hooks have the always_call option but perhaps
                # this functionality should be added to full backward hooks as well.
                for hook_id, hook in _global_forward_hooks.items():
                    if hook_id in _global_forward_hooks_always_called and hook_id not in called_always_called_hooks:
                        try:
                            hook_result = hook(self, args, result)
                            if hook_result is not None:
                                result = hook_result
                        except Exception as e:
                            warnings.warn("global module forward hook with ``always_call=True`` raised an exception "
                                          f"that was silenced as another error was raised in forward: {str(e)}")
                            continue

                for hook_id, hook in self._forward_hooks.items():
                    if hook_id in self._forward_hooks_always_called and hook_id not in called_always_called_hooks:
                        try:
                            if hook_id in self._forward_hooks_with_kwargs:
                                hook_result = hook(self, args, kwargs, result)
                            else:
                                hook_result = hook(self, args, result)
                            if hook_result is not None:
                                result = hook_result
                        except Exception as e:
                            warnings.warn("module forward hook with ``always_call=True`` raised an exception "
                                          f"that was silenced as another error was raised in forward: {str(e)}")
                            continue
                # raise exception raised in try block
                raise

        __call__ : Callable[..., Any] = _wrapped_call_impl

        def __getstate__(self):
            state = self.__dict__.copy()
            state.pop("_compiled_call_impl", None)
            return state

        def __setstate__(self, state):
            self.__dict__.update(state)

            # Support loading old checkpoints that don't have the following attrs:
            if '_forward_pre_hooks' not in self.__dict__:
                self._forward_pre_hooks = OrderedDict()
            if '_forward_pre_hooks_with_kwargs' not in self.__dict__:
                self._forward_pre_hooks_with_kwargs = OrderedDict()
            if '_forward_hooks_with_kwargs' not in self.__dict__:
                self._forward_hooks_with_kwargs = OrderedDict()
            if '_forward_hooks_always_called' not in self.__dict__:
                self._forward_hooks_always_called = OrderedDict()
            if '_state_dict_hooks' not in self.__dict__:
                self._state_dict_hooks = OrderedDict()
            if '_state_dict_pre_hooks' not in self.__dict__:
                self._state_dict_pre_hooks = OrderedDict()
            if '_load_state_dict_pre_hooks' not in self.__dict__:
                self._load_state_dict_pre_hooks = OrderedDict()
            if '_load_state_dict_post_hooks' not in self.__dict__:
                self._load_state_dict_post_hooks = OrderedDict()
            if '_non_persistent_buffers_set' not in self.__dict__:
                self._non_persistent_buffers_set = set()
            if '_is_full_backward_hook' not in self.__dict__:
                self._is_full_backward_hook = None
            if '_backward_pre_hooks' not in self.__dict__:
                self._backward_pre_hooks = OrderedDict()

        # On the return type:
        # We choose to return `Any` in the `__getattr__` type signature instead of a more strict `Union[Tensor, Module]`.
        # This is done for better interop with various type checkers for the end users.
        # Having a stricter return type doesn't play nicely with `register_buffer()` and forces
        # people to excessively use type-ignores, asserts, casts, etc.
        # See full discussion on the problems with returning `Union` here
        # https://github.com/microsoft/pyright/issues/4213
        def __getattr__(self, name: str) -> Any:
            if '_parameters' in self.__dict__:
                _parameters = self.__dict__['_parameters']
                if name in _parameters:
                    return _parameters[name]
            if '_buffers' in self.__dict__:
                _buffers = self.__dict__['_buffers']
                if name in _buffers:
                    return _buffers[name]
            if '_modules' in self.__dict__:
                modules = self.__dict__['_modules']
                if name in modules:
                    return modules[name]
            raise AttributeError(f"'{type(self).__name__}' object has no attribute '{name}'")

        def __setattr__(self, name: str, value: Union[Tensor, 'Module']) -> None:
            def remove_from(*dicts_or_sets):
                for d in dicts_or_sets:
                    if name in d:
                        if isinstance(d, dict):
                            del d[name]
                        else:
                            d.discard(name)

            params = self.__dict__.get('_parameters')
            if isinstance(value, Parameter):
                if params is None:
                    raise AttributeError(
                        "cannot assign parameters before Module.__init__() call")
                remove_from(self.__dict__, self._buffers, self._modules, self._non_persistent_buffers_set)
                self.register_parameter(name, value)
            elif params is not None and name in params:
                if value is not None:
                    raise TypeError(f"cannot assign '{torch.typename(value)}' as parameter '{name}' "
                                    "(torch.nn.Parameter or None expected)"
                                    )
                self.register_parameter(name, value)
            else:
                modules = self.__dict__.get('_modules')
                if isinstance(value, Module):
                    if modules is None:
                        raise AttributeError(
                            "cannot assign module before Module.__init__() call")
                    remove_from(self.__dict__, self._parameters, self._buffers, self._non_persistent_buffers_set)
                    for hook in _global_module_registration_hooks.values():
                        output = hook(self, name, value)
                        if output is not None:
                            value = output
                    modules[name] = value
                elif modules is not None and name in modules:
                    if value is not None:
                        raise TypeError(f"cannot assign '{torch.typename(value)}' as child module '{name}' "
                                        "(torch.nn.Module or None expected)"
                                        )
                    for hook in _global_module_registration_hooks.values():
                        output = hook(self, name, value)
                        if output is not None:
                            value = output
                    modules[name] = value
                else:
                    buffers = self.__dict__.get('_buffers')
                    if buffers is not None and name in buffers:
                        if value is not None and not isinstance(value, torch.Tensor):
                            raise TypeError(f"cannot assign '{torch.typename(value)}' as buffer '{name}' "
                                            "(torch.Tensor or None expected)"
                                            )
                        for hook in _global_buffer_registration_hooks.values():
                            output = hook(self, name, value)
                            if output is not None:
                                value = output
                        buffers[name] = value
                    else:
                        super().__setattr__(name, value)

        def __delattr__(self, name):
            if name in self._parameters:
                del self._parameters[name]
            elif name in self._buffers:
                del self._buffers[name]
                self._non_persistent_buffers_set.discard(name)
            elif name in self._modules:
                del self._modules[name]
            else:
                super().__delattr__(name)

        def _register_state_dict_hook(self, hook):
            r"""These hooks will be called with arguments: `self`, `state_dict`,
            `prefix`, `local_metadata`, after the `state_dict` of `self` is set.
            Note that only parameters and buffers of `self` or its children are
            guaranteed to exist in `state_dict`. The hooks may modify `state_dict`
            inplace or return a new one.
            """
            handle = hooks.RemovableHandle(self._state_dict_hooks)
            self._state_dict_hooks[handle.id] = hook
            return handle

        def register_state_dict_pre_hook(self, hook):
            r"""These hooks will be called with arguments: ``self``, ``prefix``,
            and ``keep_vars`` before calling ``state_dict`` on ``self``. The registered
            hooks can be used to perform pre-processing before the ``state_dict``
            call is made.
            """
            handle = hooks.RemovableHandle(self._state_dict_pre_hooks)
            self._state_dict_pre_hooks[handle.id] = hook
            return handle

        def _save_to_state_dict(self, destination, prefix, keep_vars):
            r"""Saves module state to `destination` dictionary, containing a state
            of the module, but not its descendants. This is called on every
            submodule in :meth:`~torch.nn.Module.state_dict`.

            In rare cases, subclasses can achieve class-specific behavior by
            overriding this method with custom logic.

            Args:
                destination (dict): a dict where state will be stored
                prefix (str): the prefix for parameters and buffers used in this
                    module
            """
            for name, param in self._parameters.items():
                if param is not None:
                    destination[prefix + name] = param if keep_vars else param.detach()
            for name, buf in self._buffers.items():
                if buf is not None and name not in self._non_persistent_buffers_set:
                    destination[prefix + name] = buf if keep_vars else buf.detach()
            extra_state_key = prefix + _EXTRA_STATE_KEY_SUFFIX
            if getattr(self.__class__, "get_extra_state", Module.get_extra_state) is not Module.get_extra_state:
                destination[extra_state_key] = self.get_extra_state()

        # The user can pass an optional arbitrary mappable object to `state_dict`, in which case `state_dict` returns
        # back that same object. But if they pass nothing, an `OrderedDict` is created and returned.
        T_destination = TypeVar('T_destination', bound=Dict[str, Any])

        @overload
        def state_dict(self, *, destination: T_destination, prefix: str = ..., keep_vars: bool = ...) -> T_destination:
            ...

        @overload
        def state_dict(self, *, prefix: str = ..., keep_vars: bool = ...) -> Dict[str, Any]:
            ...

        # TODO: Change `*args` to `*` and remove the corresponding warning in docs when BC allows.
        # Also remove the logic for arg parsing together.
        def state_dict(self, *args, destination=None, prefix='', keep_vars=False):
            r"""Returns a dictionary containing references to the whole state of the module.

            Both parameters and persistent buffers (e.g. running averages) are
            included. Keys are corresponding parameter and buffer names.
            Parameters and buffers set to ``None`` are not included.

            .. note::
                The returned object is a shallow copy. It contains references
                to the module's parameters and buffers.

            .. warning::
                Currently ``state_dict()`` also accepts positional arguments for
                ``destination``, ``prefix`` and ``keep_vars`` in order. However,
                this is being deprecated and keyword arguments will be enforced in
                future releases.

            .. warning::
                Please avoid the use of argument ``destination`` as it is not
                designed for end-users.

            Args:
                destination (dict, optional): If provided, the state of module will
                    be updated into the dict and the same object is returned.
                    Otherwise, an ``OrderedDict`` will be created and returned.
                    Default: ``None``.
                prefix (str, optional): a prefix added to parameter and buffer
                    names to compose the keys in state_dict. Default: ``''``.
                keep_vars (bool, optional): by default the :class:`~torch.Tensor` s
                    returned in the state dict are detached from autograd. If it's
                    set to ``True``, detaching will not be performed.
                    Default: ``False``.

            Returns:
                dict:
                    a dictionary containing a whole state of the module

            Example::

                >>> # xdoctest: +SKIP("undefined vars")
                >>> module.state_dict().keys()
                ['bias', 'weight']

            """

            # TODO: Remove `args` and the parsing logic when BC allows.
            if len(args) > 0:
                if destination is None:
                    destination = args[0]
                if len(args) > 1 and prefix == '':
                    prefix = args[1]
                if len(args) > 2 and keep_vars is False:
                    keep_vars = args[2]
                # DeprecationWarning is ignored by default
                warnings.warn(
                    "Positional args are being deprecated, use kwargs instead. Refer to "
                    "https://pytorch.org/docs/master/generated/torch.nn.Module.html#torch.nn.Module.state_dict"
                    " for details.")

            if destination is None:
                destination = OrderedDict()
                destination._metadata = OrderedDict()

            local_metadata = dict(version=self._version)
            if hasattr(destination, "_metadata"):
                destination._metadata[prefix[:-1]] = local_metadata

            for hook in self._state_dict_pre_hooks.values():
                hook(self, prefix, keep_vars)
            self._save_to_state_dict(destination, prefix, keep_vars)
            for name, module in self._modules.items():
                if module is not None:
                    module.state_dict(destination=destination, prefix=prefix + name + '.', keep_vars=keep_vars)
            for hook in self._state_dict_hooks.values():
                hook_result = hook(self, destination, prefix, local_metadata)
                if hook_result is not None:
                    destination = hook_result
            return destination

        def _register_load_state_dict_pre_hook(self, hook, with_module=False):
            r"""These hooks will be called with arguments: `state_dict`, `prefix`,
            `local_metadata`, `strict`, `missing_keys`, `unexpected_keys`,
            `error_msgs`, before loading `state_dict` into `self`. These arguments
            are exactly the same as those of `_load_from_state_dict`.

            If ``with_module`` is ``True``, then the first argument to the hook is
            an instance of the module.

            Arguments:
                hook (Callable): Callable hook that will be invoked before
                    loading the state dict.
                with_module (bool, optional): Whether or not to pass the module
                    instance to the hook as the first parameter.
            """
            handle = hooks.RemovableHandle(self._load_state_dict_pre_hooks)
            self._load_state_dict_pre_hooks[handle.id] = _WrappedHook(hook, self if with_module else None)
            return handle

        def register_load_state_dict_post_hook(self, hook):
            r"""Registers a post hook to be run after module's ``load_state_dict``
            is called.

            It should have the following signature::
                hook(module, incompatible_keys) -> None

            The ``module`` argument is the current module that this hook is registered
            on, and the ``incompatible_keys`` argument is a ``NamedTuple`` consisting
            of attributes ``missing_keys`` and ``unexpected_keys``. ``missing_keys``
            is a ``list`` of ``str`` containing the missing keys and
            ``unexpected_keys`` is a ``list`` of ``str`` containing the unexpected keys.

            The given incompatible_keys can be modified inplace if needed.

            Note that the checks performed when calling :func:`load_state_dict` with
            ``strict=True`` are affected by modifications the hook makes to
            ``missing_keys`` or ``unexpected_keys``, as expected. Additions to either
            set of keys will result in an error being thrown when ``strict=True``, and
            clearing out both missing and unexpected keys will avoid an error.

            Returns:
                :class:`torch.utils.hooks.RemovableHandle`:
                    a handle that can be used to remove the added hook by calling
                    ``handle.remove()``
            """
            handle = hooks.RemovableHandle(self._load_state_dict_post_hooks)
            self._load_state_dict_post_hooks[handle.id] = hook
            return handle

        def _load_from_state_dict(self, state_dict, prefix, local_metadata, strict,
                                  missing_keys, unexpected_keys, error_msgs):
            r"""Copies parameters and buffers from :attr:`state_dict` into only
            this module, but not its descendants. This is called on every submodule
            in :meth:`~torch.nn.Module.load_state_dict`. Metadata saved for this
            module in input :attr:`state_dict` is provided as :attr:`local_metadata`.
            For state dicts without metadata, :attr:`local_metadata` is empty.
            Subclasses can achieve class-specific backward compatible loading using
            the version number at `local_metadata.get("version", None)`.
            Additionally, :attr:`local_metadata` can also contain the key
            `assign_to_params_buffers` that indicates whether keys should be
            assigned their corresponding tensor in the state_dict.

            .. note::
                :attr:`state_dict` is not the same object as the input
                :attr:`state_dict` to :meth:`~torch.nn.Module.load_state_dict`. So
                it can be modified.

            Args:
                state_dict (dict): a dict containing parameters and
                    persistent buffers.
                prefix (str): the prefix for parameters and buffers used in this
                    module
                local_metadata (dict): a dict containing the metadata for this module.
                    See
                strict (bool): whether to strictly enforce that the keys in
                    :attr:`state_dict` with :attr:`prefix` match the names of
                    parameters and buffers in this module
                missing_keys (list of str): if ``strict=True``, add missing keys to
                    this list
                unexpected_keys (list of str): if ``strict=True``, add unexpected
                    keys to this list
                error_msgs (list of str): error messages should be added to this
                    list, and will be reported together in
                    :meth:`~torch.nn.Module.load_state_dict`
            """
            for hook in self._load_state_dict_pre_hooks.values():
                hook(state_dict, prefix, local_metadata, strict, missing_keys, unexpected_keys, error_msgs)

            persistent_buffers = {k: v for k, v in self._buffers.items() if k not in self._non_persistent_buffers_set}
            local_name_params = itertools.chain(self._parameters.items(), persistent_buffers.items())
            local_state = {k: v for k, v in local_name_params if v is not None}
            assign_to_params_buffers = local_metadata.get("assign_to_params_buffers", False)

            for name, param in local_state.items():
                key = prefix + name
                if key in state_dict:
                    input_param = state_dict[key]
                    if not torch.overrides.is_tensor_like(input_param):
                        error_msgs.append(f'While copying the parameter named "{key}", '
                                          'expected torch.Tensor or Tensor-like object from checkpoint but '
                                          f'received {type(input_param)}'
                                          )
                        continue

                    # This is used to avoid copying uninitialized parameters into
                    # non-lazy modules, since they dont have the hook to do the checks
                    # in such case, it will error when accessing the .shape attribute.
                    is_param_lazy = torch.nn.parameter.is_lazy(param)
                    # Backward compatibility: loading 1-dim tensor from 0.3.* to version 0.4+
                    if not is_param_lazy and len(param.shape) == 0 and len(input_param.shape) == 1:
                        input_param = input_param[0]

                    if not is_param_lazy and input_param.shape != param.shape:
                        # local shape should match the one in checkpoint
                        error_msgs.append('size mismatch for {}: copying a param with shape {} from checkpoint, '
                                          'the shape in current model is {}.'
                                          .format(key, input_param.shape, param.shape))
                        continue

                    if param.is_meta and not input_param.is_meta and not assign_to_params_buffers:
                        warnings.warn(f'for {key}: copying from a non-meta parameter in the checkpoint to a meta '
                                      'parameter in the current model, which is a no-op. (Did you mean to '
                                      'pass `assign=True` to assign items in the state dictionary to their '
                                      'corresponding key in the module instead of copying them in place?)')

                    try:
                        with torch.no_grad():
                            if assign_to_params_buffers:
                                # Shape checks are already done above
                                if (isinstance(param, torch.nn.Parameter) and
                                        not isinstance(input_param, torch.nn.Parameter)):
                                    setattr(self, name, torch.nn.Parameter(input_param))
                                else:
                                    setattr(self, name, input_param)
                            else:
                                param.copy_(input_param)
                    except Exception as ex:
                        error_msgs.append(f'While copying the parameter named "{key}", '
                                          f'whose dimensions in the model are {param.size()} and '
                                          f'whose dimensions in the checkpoint are {input_param.size()}, '
                                          f'an exception occurred : {ex.args}.'
                                          )
                elif strict:
                    missing_keys.append(key)

            extra_state_key = prefix + _EXTRA_STATE_KEY_SUFFIX
            if getattr(self.__class__, "set_extra_state", Module.set_extra_state) is not Module.set_extra_state:
                if extra_state_key in state_dict:
                    self.set_extra_state(state_dict[extra_state_key])
                elif strict:
                    missing_keys.append(extra_state_key)
            elif strict and (extra_state_key in state_dict):
                unexpected_keys.append(extra_state_key)

            if strict:
                for key in state_dict.keys():
                    if key.startswith(prefix) and key != extra_state_key:
                        input_name = key[len(prefix):]
                        input_name = input_name.split('.', 1)[0]  # get the name of param/buffer/child
                        if input_name not in self._modules and input_name not in local_state:
                            unexpected_keys.append(key)

        def load_state_dict(self, state_dict: Mapping[str, Any],
                            strict: bool = True, assign: bool = False):
            r"""Copies parameters and buffers from :attr:`state_dict` into
            this module and its descendants. If :attr:`strict` is ``True``, then
            the keys of :attr:`state_dict` must exactly match the keys returned
            by this module's :meth:`~torch.nn.Module.state_dict` function.

            .. warning::
                If :attr:`assign` is ``True`` the optimizer must be created after
                the call to :attr:`load_state_dict`.

            Args:
                state_dict (dict): a dict containing parameters and
                    persistent buffers.
                strict (bool, optional): whether to strictly enforce that the keys
                    in :attr:`state_dict` match the keys returned by this module's
                    :meth:`~torch.nn.Module.state_dict` function. Default: ``True``
                assign (bool, optional): whether to assign items in the state
                    dictionary to their corresponding keys in the module instead
                    of copying them inplace into the module's current parameters and buffers.
                    When ``False``, the properties of the tensors in the current
                    module are preserved while when ``True``, the properties of the
                    Tensors in the state dict are preserved.
                    Default: ``False``

            Returns:
                ``NamedTuple`` with ``missing_keys`` and ``unexpected_keys`` fields:
                    * **missing_keys** is a list of str containing the missing keys
                    * **unexpected_keys** is a list of str containing the unexpected keys

            Note:
                If a parameter or buffer is registered as ``None`` and its corresponding key
                exists in :attr:`state_dict`, :meth:`load_state_dict` will raise a
                ``RuntimeError``.
            """
            if not isinstance(state_dict, Mapping):
                raise TypeError(f"Expected state_dict to be dict-like, got {type(state_dict)}.")

            missing_keys: List[str] = []
            unexpected_keys: List[str] = []
            error_msgs: List[str] = []

            # copy state_dict so _load_from_state_dict can modify it
            metadata = getattr(state_dict, '_metadata', None)
            state_dict = OrderedDict(state_dict)
            if metadata is not None:
                # mypy isn't aware that "_metadata" exists in state_dict
                state_dict._metadata = metadata  # type: ignore[attr-defined]

            def load(module, local_state_dict, prefix=''):
                local_metadata = {} if metadata is None else metadata.get(prefix[:-1], {})
                if assign:
                    local_metadata['assign_to_params_buffers'] = assign
                module._load_from_state_dict(
                    local_state_dict, prefix, local_metadata, True, missing_keys, unexpected_keys, error_msgs)
                for name, child in module._modules.items():
                    if child is not None:
                        child_prefix = prefix + name + '.'
                        child_state_dict = {k: v for k, v in local_state_dict.items() if k.startswith(child_prefix)}
                        load(child, child_state_dict, child_prefix)

                # Note that the hook can modify missing_keys and unexpected_keys.
                incompatible_keys = _IncompatibleKeys(missing_keys, unexpected_keys)
                for hook in module._load_state_dict_post_hooks.values():
                    out = hook(module, incompatible_keys)
                    assert out is None, (
                        "Hooks registered with ``register_load_state_dict_post_hook`` are not"
                        "expected to return new values, if incompatible_keys need to be modified,"
                        "it should be done inplace."
                    )

            load(self, state_dict)
            del load

            if strict:
                if len(unexpected_keys) > 0:
                    error_msgs.insert(
                        0, 'Unexpected key(s) in state_dict: {}. '.format(
                            ', '.join(f'"{k}"' for k in unexpected_keys)))
                if len(missing_keys) > 0:
                    error_msgs.insert(
                        0, 'Missing key(s) in state_dict: {}. '.format(
                            ', '.join(f'"{k}"' for k in missing_keys)))

            if len(error_msgs) > 0:
                raise RuntimeError('Error(s) in loading state_dict for {}:\n\t{}'.format(
                                   self.__class__.__name__, "\n\t".join(error_msgs)))
            return _IncompatibleKeys(missing_keys, unexpected_keys)

        def _named_members(self, get_members_fn, prefix='', recurse=True, remove_duplicate: bool = True):
            r"""Helper method for yielding various names + members of modules."""
            memo = set()
            modules = self.named_modules(prefix=prefix, remove_duplicate=remove_duplicate) if recurse else [(prefix, self)]
            for module_prefix, module in modules:
                members = get_members_fn(module)
                for k, v in members:
                    if v is None or v in memo:
                        continue
                    if remove_duplicate:
                        memo.add(v)
                    name = module_prefix + ('.' if module_prefix else '') + k
                    yield name, v

        def parameters(self, recurse: bool = True) -> Iterator[Parameter]:
            r"""Returns an iterator over module parameters.

            This is typically passed to an optimizer.

            Args:
                recurse (bool): if True, then yields parameters of this module
                    and all submodules. Otherwise, yields only parameters that
                    are direct members of this module.

            Yields:
                Parameter: module parameter

            Example::

                >>> # xdoctest: +SKIP("undefined vars")
                >>> for param in model.parameters():
                >>>     print(type(param), param.size())
                <class 'torch.Tensor'> (20L,)
                <class 'torch.Tensor'> (20L, 1L, 5L, 5L)

            """
            for name, param in self.named_parameters(recurse=recurse):
                yield param

        def named_parameters(
                self,
                prefix: str = '',
                recurse: bool = True,
                remove_duplicate: bool = True
        ) -> Iterator[Tuple[str, Parameter]]:
            r"""Returns an iterator over module parameters, yielding both the
            name of the parameter as well as the parameter itself.

            Args:
                prefix (str): prefix to prepend to all parameter names.
                recurse (bool): if True, then yields parameters of this module
                    and all submodules. Otherwise, yields only parameters that
                    are direct members of this module.
                remove_duplicate (bool, optional): whether to remove the duplicated
                    parameters in the result. Defaults to True.

            Yields:
                (str, Parameter): Tuple containing the name and parameter

            Example::

                >>> # xdoctest: +SKIP("undefined vars")
                >>> for name, param in self.named_parameters():
                >>>     if name in ['bias']:
                >>>         print(param.size())

            """
            gen = self._named_members(
                lambda module: module._parameters.items(),
                prefix=prefix, recurse=recurse, remove_duplicate=remove_duplicate)
            yield from gen

        def buffers(self, recurse: bool = True) -> Iterator[Tensor]:
            r"""Returns an iterator over module buffers.

            Args:
                recurse (bool): if True, then yields buffers of this module
                    and all submodules. Otherwise, yields only buffers that
                    are direct members of this module.

            Yields:
                torch.Tensor: module buffer

            Example::

                >>> # xdoctest: +SKIP("undefined vars")
                >>> for buf in model.buffers():
                >>>     print(type(buf), buf.size())
                <class 'torch.Tensor'> (20L,)
                <class 'torch.Tensor'> (20L, 1L, 5L, 5L)

            """
            for _, buf in self.named_buffers(recurse=recurse):
                yield buf

        def named_buffers(self, prefix: str = '', recurse: bool = True, remove_duplicate: bool = True) -> Iterator[Tuple[str, Tensor]]:
            r"""Returns an iterator over module buffers, yielding both the
            name of the buffer as well as the buffer itself.

            Args:
                prefix (str): prefix to prepend to all buffer names.
                recurse (bool, optional): if True, then yields buffers of this module
                    and all submodules. Otherwise, yields only buffers that
                    are direct members of this module. Defaults to True.
                remove_duplicate (bool, optional): whether to remove the duplicated buffers in the result. Defaults to True.

            Yields:
                (str, torch.Tensor): Tuple containing the name and buffer

            Example::

                >>> # xdoctest: +SKIP("undefined vars")
                >>> for name, buf in self.named_buffers():
                >>>     if name in ['running_var']:
                >>>         print(buf.size())

            """
            gen = self._named_members(
                lambda module: module._buffers.items(),
                prefix=prefix, recurse=recurse, remove_duplicate=remove_duplicate)
            yield from gen

        def children(self) -> Iterator['Module']:
            r"""Returns an iterator over immediate children modules.

            Yields:
                Module: a child module
            """
            for name, module in self.named_children():
                yield module

        def named_children(self) -> Iterator[Tuple[str, 'Module']]:
            r"""Returns an iterator over immediate children modules, yielding both
            the name of the module as well as the module itself.

            Yields:
                (str, Module): Tuple containing a name and child module

            Example::

                >>> # xdoctest: +SKIP("undefined vars")
                >>> for name, module in model.named_children():
                >>>     if name in ['conv4', 'conv5']:
                >>>         print(module)

            """
            memo = set()
            for name, module in self._modules.items():
                if module is not None and module not in memo:
                    memo.add(module)
                    yield name, module

        def modules(self) -> Iterator['Module']:
            r"""Returns an iterator over all modules in the network.

            Yields:
                Module: a module in the network

            Note:
                Duplicate modules are returned only once. In the following
                example, ``l`` will be returned only once.

            Example::

                >>> l = nn.Linear(2, 2)
                >>> net = nn.Sequential(l, l)
                >>> for idx, m in enumerate(net.modules()):
                ...     print(idx, '->', m)

                0 -> Sequential(
                  (0): Linear(in_features=2, out_features=2, bias=True)
                  (1): Linear(in_features=2, out_features=2, bias=True)
                )
                1 -> Linear(in_features=2, out_features=2, bias=True)

            """
            for _, module in self.named_modules():
                yield module

        def named_modules(self, memo: Optional[Set['Module']] = None, prefix: str = '', remove_duplicate: bool = True):
            r"""Returns an iterator over all modules in the network, yielding
            both the name of the module as well as the module itself.

            Args:
                memo: a memo to store the set of modules already added to the result
                prefix: a prefix that will be added to the name of the module
                remove_duplicate: whether to remove the duplicated module instances in the result
                    or not

            Yields:
                (str, Module): Tuple of name and module

            Note:
                Duplicate modules are returned only once. In the following
                example, ``l`` will be returned only once.

            Example::

                >>> l = nn.Linear(2, 2)
                >>> net = nn.Sequential(l, l)
                >>> for idx, m in enumerate(net.named_modules()):
                ...     print(idx, '->', m)

                0 -> ('', Sequential(
                  (0): Linear(in_features=2, out_features=2, bias=True)
                  (1): Linear(in_features=2, out_features=2, bias=True)
                ))
                1 -> ('0', Linear(in_features=2, out_features=2, bias=True))

            """

            if memo is None:
                memo = set()
            if self not in memo:
                if remove_duplicate:
                    memo.add(self)
                yield prefix, self
                for name, module in self._modules.items():
                    if module is None:
                        continue
                    submodule_prefix = prefix + ('.' if prefix else '') + name
                    yield from module.named_modules(memo, submodule_prefix, remove_duplicate)

        def train(self: T, mode: bool = True) -> T:
            r"""Sets the module in training mode.

            This has any effect only on certain modules. See documentations of
            particular modules for details of their behaviors in training/evaluation
            mode, if they are affected, e.g. :class:`Dropout`, :class:`BatchNorm`,
            etc.

            Args:
                mode (bool): whether to set training mode (``True``) or evaluation
                             mode (``False``). Default: ``True``.

            Returns:
                Module: self
            """
            if not isinstance(mode, bool):
                raise ValueError("training mode is expected to be boolean")
            self.training = mode
            for module in self.children():
                module.train(mode)
            return self

        def eval(self: T) -> T:
            r"""Sets the module in evaluation mode.

            This has any effect only on certain modules. See documentations of
            particular modules for details of their behaviors in training/evaluation
            mode, if they are affected, e.g. :class:`Dropout`, :class:`BatchNorm`,
            etc.

            This is equivalent with :meth:`self.train(False) <torch.nn.Module.train>`.

            See :ref:`locally-disable-grad-doc` for a comparison between
            `.eval()` and several similar mechanisms that may be confused with it.

            Returns:
                Module: self
            """
            return self.train(False)

        def requires_grad_(self: T, requires_grad: bool = True) -> T:
            r"""Change if autograd should record operations on parameters in this
            module.

            This method sets the parameters' :attr:`requires_grad` attributes
            in-place.

            This method is helpful for freezing part of the module for finetuning
            or training parts of a model individually (e.g., GAN training).

            See :ref:`locally-disable-grad-doc` for a comparison between
            `.requires_grad_()` and several similar mechanisms that may be confused with it.

            Args:
                requires_grad (bool): whether autograd should record operations on
                                      parameters in this module. Default: ``True``.

            Returns:
                Module: self
            """
            for p in self.parameters():
                p.requires_grad_(requires_grad)
            return self

        def zero_grad(self, set_to_none: bool = True) -> None:
            r"""Resets gradients of all model parameters. See similar function
            under :class:`torch.optim.Optimizer` for more context.

            Args:
                set_to_none (bool): instead of setting to zero, set the grads to None.
                    See :meth:`torch.optim.Optimizer.zero_grad` for details.
            """
            if getattr(self, '_is_replica', False):
                warnings.warn(
                    "Calling .zero_grad() from a module created with nn.DataParallel() has no effect. "
                    "The parameters are copied (in a differentiable manner) from the original module. "
                    "This means they are not leaf nodes in autograd and so don't accumulate gradients. "
                    "If you need gradients in your forward method, consider using autograd.grad instead.")

            for p in self.parameters():
                if p.grad is not None:
                    if set_to_none:
                        p.grad = None
                    else:
                        if p.grad.grad_fn is not None:
                            p.grad.detach_()
                        else:
                            p.grad.requires_grad_(False)
                        p.grad.zero_()

        def share_memory(self: T) -> T:
            r"""See :meth:`torch.Tensor.share_memory_`"""
            return self._apply(lambda t: t.share_memory_())

        def _get_name(self):
            return self.__class__.__name__

        def extra_repr(self) -> str:
            r"""Set the extra representation of the module

            To print customized extra information, you should re-implement
            this method in your own modules. Both single-line and multi-line
            strings are acceptable.
            """
            return ''

        def __repr__(self):
            # We treat the extra repr like the sub-module, one item per line
            extra_lines = []
            extra_repr = self.extra_repr()
            # empty string will be split into list ['']
            if extra_repr:
                extra_lines = extra_repr.split('\n')
            child_lines = []
            for key, module in self._modules.items():
                mod_str = repr(module)
                mod_str = _addindent(mod_str, 2)
                child_lines.append('(' + key + '): ' + mod_str)
            lines = extra_lines + child_lines

            main_str = self._get_name() + '('
            if lines:
                # simple one-liner info, which most builtin Modules will use
                if len(extra_lines) == 1 and not child_lines:
                    main_str += extra_lines[0]
                else:
                    main_str += '\n  ' + '\n  '.join(lines) + '\n'

            main_str += ')'
            return main_str

        def __dir__(self):
            module_attrs = dir(self.__class__)
            attrs = list(self.__dict__.keys())
            parameters = list(self._parameters.keys())
            modules = list(self._modules.keys())
            buffers = list(self._buffers.keys())
            keys = module_attrs + attrs + parameters + modules + buffers

            # Eliminate attrs that are not legal Python variable names
            keys = [key for key in keys if not key[0].isdigit()]

            return sorted(keys)

        def _replicate_for_data_parallel(self):
            replica = self.__new__(type(self))
            replica.__dict__ = self.__dict__.copy()

            # replicas do not have parameters themselves, the replicas reference the original
            # module.
            replica._parameters = OrderedDict()
            replica._buffers = replica._buffers.copy()
            replica._modules = replica._modules.copy()
            replica._is_replica = True  # type: ignore[assignment]

            return replica

        def compile(self, *args, **kwargs):
            """
            Compile this Module's forward using :func:`torch.compile`.

            This Module's `__call__` method is compiled and all arguments are passed as-is
            to :func:`torch.compile`.

            See :func:`torch.compile` for details on the arguments for this function.
            """
            self._compiled_call_impl = torch.compile(self._call_impl, *args, **kwargs)

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