python MQTT订阅消息提取

最近入门物联网项目，同过EMQ搭建MQTT服务端，python客户端进行发布和订阅，想将订阅的信息在web前段显示或者存入数据库，但是发现订阅到的信息无法提取，想问问订阅的信息“msg”如何return或者提取出来？订阅代码如下

# python3.6

from encodings import utf_8
from http import client
from multiprocessing.connection import Client
import random

from paho.mqtt import client as mqtt_client


broker = '127.0.0.1'
port = 1883
topic = "/LG210/up"
# generate client ID with pub prefix randomly
client_id = f'python-mqtt-{random.randint(0, 100)}'
# client_id = 'e2845cea-fa96-4ae1-8c50-9dab75781a1c1645090157775'

def connect_mqtt() -> mqtt_client:
    def on_connect(client, userdata, flags, rc):
        if rc == 0:
            print("Connected to MQTT Broker!")
        else:
            print("Failed to connect, return code %d\n", rc)

    client = mqtt_client.Client(client_id)
    client.on_connect = on_connect
    client.connect(broker, port)
    return client


def subscribe(client: mqtt_client):
    def on_message(client, userdata, msg):
        print(f"Received `{[msg.payload]}` from `{msg.topic}` topic")
        # return msg
    client.subscribe(topic)
    client.on_message = on_message



def run():
    client = connect_mqtt()
    data = subscribe(client)
    client.loop_forever()
    

if __name__ == '__main__':
    run()

尝试return，但是如法返回