docs: def _handle_command_response(self, res, event):
          """Either send a message (choosing between rtm and postMessage) or ignore the response.
  
          :param event: a slacker event dict
          :param res: a string, a dict, or None.
            See the command docstring for what these represent.
          """
  
          response_handler = None
  
          if isinstance(res, basestring):
              response_handler = functools.partial(self._send_rtm_message, event['channel'])
          elif isinstance(res, dict):
              response_handler = self._send_api_message
  
          if response_handler is not None:
              response_handler(res)