Python3.6:如何在不使用类的情况下使用SelectConnection适配器创建pika消费者？

import pika
from pika.adapters import SelectConnection

def callback(ch, method, properties, body):
    print("Received message:", body)

connection = pika.SelectConnection(parameters)
channel = connection.channel()

parameters = pika.ConnectionParameters(host='localhost', port=5672)

channel.queue_declare(queue='my_queue')
channel.basic_consume(queue='my_queue', on_message_callback=callback, auto_ack=True)

connection.ioloop.start()

import pika
from pika.adapters import SelectConnection

def callback(ch, method, properties, body):
    print("Received message:", body)

parameters = pika.ConnectionParameters(host='localhost', port=5672)
connection = pika.SelectConnection(parameters)
channel = connection.channel()
channel.queue_declare(queue='my_queue')
channel.basic_consume(queue='my_queue', on_message_callback=callback, auto_ack=True)
connection.ioloop.start()