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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def _publish(self, msg):
 """Publish, handling retries, a message in the queue. :param msg: Object which represents the message to be sent in the queue. Note that this object should be serializable in the configured format (by default JSON). """

        connection = self._connection.clone()
        publish = connection.ensure(self.producer, self.producer.publish,
                                    errback=self.__error_callback,
                                    max_retries=MQ_PRODUCER_MAX_RETRIES)
        publish(json.dumps(msg), exchange=self._exchange,
                routing_key=self._routing_key, declare=[self._queue])
        logging.debug('Publisher: message sent: %s', msg)