Python proxy client connections requiring authe...

#!/use/bin/env python
#-*- coding: utf-8 -*-
'''urllib2_proxy_handler.py
   @author: Zhang Kai
   @note: Example for using urllib2.urlopen() with a proxy server requiring authentication.
   @date: 30/07/2013
'''
import urllib2

URI = "http://www.baidu.com"
HTTP_PROXY_SERVER = "135.33.33.33"
HTTP_PROXY_PORT = "80"
HTTP_PROXY_REALM = HTTP_PROXY_SERVER #Worked in my(limited) testing environment.
HTTP_PROXY_USER = "apprentice"
HTTP_PROXY_PASSWD = "xxx"
#Next Line = "http://username:password@someproxyserver.com:3128"
HTTP_PROXY_FULL_AUTH_STRING = "http://%s:%s@%s:%s" %(HTTP_PROXY_USER,
                                                     HTTP_PROXY_PASSWD,
                                                     HTTP_PROXY_SERVER,
                                                     HTTP_PROXY_PORT)
def open_url_no_proxy():
    urllib2.urlopen(URI)
    print "Apparent success without proxy server!"
def open_url_installed_opener():
    proxy_handler = urllib2.ProxyHandler({"http":HTTP_PROXY_FULL_AUTH_STRING})
    opener = urllib2.build_opener(proxy_handler)
    urllib2.install_opener(opener)
    urllib2.urlopen(URI)
    print "Apparent success through proxy server!"
if __name__ == "__main__":
    try:
        open_url_no_proxy()
    except Exception:
        open_url_installed_opener()

输出：