docstr: Reducer for function objects.
  
  If obj is a top-level attribute of a file-backed module, this
  reducer returns NotImplemented, making the CloudPickler fallback to
  traditional _pickle.Pickler routines to save obj. Otherwise, it reduces
  obj using a custom cloudpickle reducer designed specifically to handle
  dynamic functions.
  
  As opposed to cloudpickle.py, There no special handling for builtin
  pypy functions because cloudpickle_fast is CPython-specific.
code: def _function_reduce(self, obj):
      """Reducer for function objects.
  
      If obj is a top-level attribute of a file-backed module, this
      reducer returns NotImplemented, making the CloudPickler fallback to
      traditional _pickle.Pickler routines to save obj. Otherwise, it reduces
      obj using a custom cloudpickle reducer designed specifically to handle
      dynamic functions.
  
      As opposed to cloudpickle.py, There no special handling for builtin
      pypy functions because cloudpickle_fast is CPython-specific.
      """
      if _is_importable(obj):
          return NotImplemented
      else:
          return self._dynamic_function_reduce(obj)
  
imports: import abc
  import copyreg
  import io
  import itertools
  import logging
  import sys
  import struct
  import types
  import weakref
  import typing
  from enum import Enum
  from collections import ChainMap
  from ._compat import pickle, Pickler
  from ._cloudpickle import _extract_code_globals, _BUILTIN_TYPE_NAMES, DEFAULT_PROTOCOL, _find_imported_submodules, _get_cell_contents, _is_importable, _builtin_type, _get_or_create_tracker_id, _make_skeleton_class, _make_skeleton_enum, _extract_class_dict, dynamic_subimport, subimport, _typevar_reduce, _get_bases, _make_cell, _make_empty_cell, CellType, _is_parametrized_type_hint, PYPY, cell_set, parametrized_type_hint_getinitargs, _create_parametrized_type_hint, builtin_code_type
label_desc: Use image node_id 2 for calling the CloudPickler obj's underlying member method code with example usage: obj._function_reduce(obj) and returns: NotImplemented, self