import paho.mqtt.client as mqtt
server = "xxxxxxxxx.com"
port = 1883
username = "xx"
password = "xxxxxxxxxxxxxxxxxxxx"
topic = "temp/f/xxxx"

client = mqtt.Client(client_id="", clean_session=True, userdata=None, protocol="MQTTv31")
client.username_pw_set(username, password)
client.connect(server, port, keepalive=120, bind_address="")

def read_temperature(device_id):
    "Read float temperature value from 1wire device DS18B20."
with open('/sys/bus/w1/devices/%s/w1_slave' % device_id) as f:
    text = f.read().strip()
    fragments = text.split()
    return float(fragments[-1][2:]) / 1000.
    time.sleep(10)
while True:
    client.publish(topic, read_temperature('28-00000531cfff'), qos=1, retain=False)
    print round(read_temperature('28-00000531cfff'),1)
    time.sleep(10)