docs: def _dispatch_message(self):
          """
          _dispatch_message
          """
          while True:
              message = self.req_queue.get()
              if message is None:
                  _logger.debug("_dispatch_message thread is terminated")
                  return
  
              if message._type != MessageType.EVENT:
                  self.__dispatch_message(message)
              elif message._type == MessageType.EVENT:
                  self.__dispatch_event_message(message)