code: def declare_consumer(self, queue, no_ack, callback, consumer_tag,
              nowait=False):
          
  
          @functools.wraps(callback)
          def _callback_decode(channel, method, header, body):
              return callback((channel, method, header, body))
  
          return self.channel.basic_consume(_callback_decode,
                                            queue=queue,
                                            no_ack=no_ack,
                                            consumer_tag=consumer_tag)
docs: Declare a consumer.