python提交post数据到远程url

import sys, urllib2, urllib
 
zipcode = "S2S 1R8"
url = 'http://www.wunderground.com/cgi-bin/findweather/getForecast'
data = urllib.urlencode([('query', zipcode)])
req = urllib2.Request(url)
fd = urllib2.urlopen(req, data)
while 1:
    data = fd.read(1024)
    if not len(data):
        break
    sys.stdout.write(data)