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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, topic, payload, qos=0, retain=False, wait=False):
 """ Sends a message through the MQTT connection :param topic: Message topic :param payload: Message content :param qos: Quality of Service :param retain: Retain flag :param wait: If True, prepares an event to wait for the message to be published :return: The local message ID, None on error """

        result = self.__mqtt.publish(topic, payload, qos, retain)
        if wait and not result[0]:
            # Publish packet sent, wait for it to return
            self.__in_flight[result[1]] = threading.Event()
            _logger.debug("Waiting for publication of %s", topic)

        return result[1]