Get latest Ikea Trådfri firmware versions

#!/usr/bin/env python
import os
import json
import urllib

file = urllib.urlopen("http://fw.ota.homesmart.ikea.net/feed/version_info.json")
data = file.read()
arr  = json.loads(data)

for i in arr:
            if 'fw_binary_url' in i:
                        url = i['fw_binary_url']
                        print (url)