def open_channel(self):
_logger.info('<STR_LIT>')<EOL>self._connection.channel(on_open_callback=self.on_channel_open)<EOL>
Open a new channel with RabbitMQ by issuing the Channel.Open RPC
        command. When RabbitMQ responds that the channel is open, the
        on_channel_open callback will be invoked by pika.