import sys
import httplib
from time import gmtime, strftime
datetime = strftime("%Y-%m-%d")+"T"+str(int(strftime("%H"))-1)+"Z"
URL = "/public/data" 
URL += "/val" # data type
URL += "/wxobs"
URL += "/all" # type
URL += "/json"
URL += "/sitelist"
URL += "?"
URL += "res=hourly"
URL += "&"
#URL += "time="+datetime
URL += "&key=74f7ac18-636f-412f-aba3-83aec4452340"
datapoint = httplib.HTTPConnection("datapoint.metoffice.gov.uk")
datapoint.request("GET", URL)

print datapoint.getresponse().read()

#http://datapoint.metoffice.gov.uk/public/data/val/wxfcs/all/xml/sitelist?res=daily&key=<API key>