A quick and dirty URL request and JSON decoding/deserialization.

py-request.py

import json
from urllib import request
from pprint import pprint


def main():
    weather_req = request.urlopen("http://api.wunderground.com/api/872a930f94a85692/conditions/q/UK/London.json")
    # read the request and decode the bytes into sensible UTF-8 strings
    weather_data = weather_req.read().decode("utf-8")
    # take a peak at the mess of it
    pprint(weather_data)
    # lets turn it into something useful by decoding it:
    weather_data = json.loads(weather_data)
    # lets just save the key we care about, "current_observation"
    weather_data = weather_data["current_observation"]
    pprint(weather_data)

    # this "useful" thing is called a `dict` in Python. We can access things by its attributes now like this:
    print(type(weather_data))
    print("\n\nRight now in {city} feels like {feels_like}.\n\n" \
            .format(city=weather_data["display_location"]["city"],
                    feels_like=weather_data["feelslike_string"]
         ))


if __name__ == '__main__':
    main()