Get last data from SCK

import pycurl, cStringIO, json

device = 139
buf = cStringIO.StringIO()

c = pycurl.Curl()
c.setopt(c.URL, 'http://data.smartcitizen.me/testjson?device={0}'.format(device))
c.setopt(c.WRITEFUNCTION, buf.write)
c.perform()

resStr = buf.getvalue()
buf.close()

obj = json.loads(resStr)
last = obj[-1]

for data in last:
    print "{0}: {1}".format(data, last[data])