code: def publish(self, message_type, client_id, client_storage, *args, **kwargs):
          
          if self.connection.connected:
              message = self.exchange.Message(
                  self.pack(message_type, client_id, client_storage, args, kwargs))
              self.exchange.publish(message, routing_key='')
docs: Publishes a message
          Uses `self.pack` instead of 'msgpack' serializer on kombu for backend consistency