temperature reading from DHT22 and putting onto RabbitMq queue

gistfile1.py

import Adafruit_DHT
import pika
import threading
from datetime import datetime
import uuid
import time
import json

sensor = Adafruit_DHT.DHT22
pin = 4

def read():
  humidity, temperature  = Adafruit_DHT.read(sensor, pin)
  current_datetime = datetime.utcnow().strftime("%Y-%m-%dT%H:%M:%S")
  if temperature is not None and humidity is not None: 
    print 'temp: {0:0.1f}C humid: {1:0.1f}% at {2}'.format(temperature, humidity, current_datetime)
    id = uuid.uuid4()

    output={
        'id':str(id), 
        'created_at':current_datetime,
        'temperature': temperature,
        'humidity': humidity
    }
    return output 
  else:
    raise ValueError('temperature and humidity data is nothing at {0}'.format(current_datetime))

connection = pika.BlockingConnection()
channel = connection.channel()
channel.queue_declare(queue='temperatures', durable=True)

#read every 10 sec and queue up the reading
while True:
  data = read()
  channel.basic_publish(exchange='', routing_key='temperatures',
      body=json.dumps(data),
      properties=pika.BasicProperties(delivery_mode=2))
  time.sleep(10)