docs: def extract_keywords(func):
      """
      Parses the keywords from the given function.
  
      :param      func | <function>
      """
      if hasattr(func, 'im_func'):
          func = func.im_func
  
      try:
          return func.func_code.co_varnames[-len(func.func_defaults):]
      except (TypeError, ValueError, IndexError):
          return tuple()