code: def boolean(cls, true_code, false_code=None):
          
          def func(response):
              if response is not None:
                  status_code = response.status
                  if status_code == true_code:
                      return True
                  if false_code is not None and status_code == false_code:
                      return False
                  raise error_for(response)
          return func
docs: Callback to validate a response code.
  
          The returned callback checks whether a given response has a
          ``status_code`` that is considered good (``true_code``) and
          raise an appropriate error if not.
  
          The optional ``false_code`` allows for a non-successful status
          code to return False instead of throwing an error. This is used,
          for example in relationship mutation to indicate that the
          relationship was not modified.
  
          Args:
  
              true_code(int): The http status code to consider as a success
  
          Keyword Args:
  
              false_code(int): The http status code to consider a failure
  
          Returns:
  
              A function that given a response returns ``True`` if the
                  response's status code matches the given code. Raises
                  a :class:`HeliumError` if the response code does not
                  match.