python获取代理IP并测试是否可用

# coding: utf-8

import urllib2
import re
import time

def getDL(page):
    url = 'http://www.xicidaili.com/nt/{}'.format(page)
    header = {
        'User-Agent':'Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/61.0.3163.100 Safari/537.36'
    }

    req=urllib2.Request(url, headers=header)
    res=urllib2.urlopen(req)
    html=res.read()

    srclist=re.findall(r'<tr class=(.|\n)*?<td>(\d+\.\d+\.\d+\.\d+)</td>(.|\n)*?<td>(\d+)</td>(.|\n)*?<td>(HTTP|HTTPS)</td>', html)
    xlist = []
    for item in srclist:
        xlist.append((item[5],item[1],item[3]))
    return xlist

def testDL(ipstr):
    proxy= urllib2.ProxyHandler({'http':"{}:{}".format(ipstr[1], ipstr[2])})
    opener=urllib2.build_opener(proxy)
    urllib2.install_opener(opener)

    try:
        testUrl = 'http://httpbin.org/ip'
        testUrl = 'http://2017.ip138.com/ic.asp'
        req=urllib2.Request(testUrl)
        res=urllib2.urlopen(req).read()
        print "********************* √ {}    -- {}".format(ipstr, res)

        with open("ok.txt","a") as f:
            f.write("{} {} {}\n".format(ipstr[0], ipstr[1], ipstr[2]))
            f.close()
    except Exception as e:
        print "******** ×, {} -- {}".format(ipstr, e)
    time.sleep(1)

def startTask():
    for page in xrange(5):
        list=getDL(page+1)
        for item in list:
            testDL(item)

if __name__ == '__main__':
    startTask()