code: def get_module_all(node):
      
      all_ = None
  
      if "__all__" in node.locals:
          assigned = next(node.igetattr("__all__"))
          if assigned is not astroid.Uninferable:
              all_ = []
              for elt in getattr(assigned, "elts", ()):
                  try:
                      elt_name = next(elt.infer())
                  except astroid.InferenceError:
                      continue
  
                  if elt_name is astroid.Uninferable:
                      continue
  
                  if isinstance(elt_name, astroid.Const) and isinstance(
                      elt_name.value, _STRING_TYPES
                  ):
                      all_.append(elt_name.value)
  
      return all_
docs: Get the contents of the ``__all__`` variable from a module.
  
      :param node: The module to get ``__all__`` from.
      :type node: astroid.nodes.Module
  
      :returns: The contents of ``__all__`` if defined. Otherwise None.
      :rtype: list(str) or None