MQTT_Client_Python

import paho.mqtt.client as mqtt #import the client1
import time

def on_connect(client, userdata, rc):
    print("Connected with result code: %s" % rc)
    client.subscribe("hello/world")

def on_message(client, userdata, message):
    print("message received " ,str(message.payload.decode("utf-8")))
    print("message topic=",message.topic)
    print("message qos=",message.qos)
    print("message retain flag=",message.retain)

def main():
    client = mqtt.Client("P1") #create new instance
#    client.on_connect = on_connect
    client.on_message=on_message #attach function to callback

    client.connect("192.168.1.39")
    client.loop_start() #start the loop
    client.subscribe("hello/world") # subscribe on topic hello/world
    time.sleep(99) # wait
    client.loop_stop() #stop the loop
if __name__ == "__main__":
    main()