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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 send_publish(self, mid, topic, payload, qos, retain, dup):
 """Send PUBLISH."""

        self.logger.debug("Send PUBLISH")
        if self.sock == NC.INVALID_SOCKET:
            return NC.ERR_NO_CONN

        #NOTE: payload may be any kind of data
        #      yet if it is a unicode string we utf8-encode it as convenience
        return self._do_send_publish(mid, utf8encode(topic), utf8encode(payload), qos, retain, dup)