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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=None, qos=0, retain=False):
 # type: (str, bytes, int, bool) -> Tuple[int, int] """ Send a message to the broker. :param topic: the topic that the message should be published on :param payload: the actual message to send. If not given, or set to None a zero length message will be used. Passing an int or float will result in the payload being converted to a string representing that number. If you wish to send a true int/float, use struct.pack() to create the payload you require. :param qos: the quality of service level to use :param retain: if set to True, the message will be set as the "last known good"/retained message for the topic :returns: Returns a tuple (result, mid), where result is MQTT_ERR_SUCCESS to indicate success or MQTT_ERR_NO_CONN if the client is not currently connected. mid is the message ID for the publish request. """

        if not self.connected:
            self.client.reconnect()

        result, mid = self.client.publish(topic, payload, qos, retain)
        if result == MQTT_ERR_SUCCESS:
            logger.debug('Published topic {0}: {1}'.format(topic, payload))
        else:
            logger.error('Error {0} publishing topic {1}'
                         .format(result, topic))

        return (result, mid)