北漂的女孩

python抓取页面是实现方式：

#!/usr/bin/python
# -*- coding: utf-8 -*-
import urllib2
import cookielib

url = 'http://www.baidu.com'
print '第一种方法'
response1 = urllib2.urlopen(url)
print response1.getcode()
print len(response1.read())

print "第二种方法"
request = urllib2.Request(url)
request.add_header("user_agent","Mozilla/5.0")
response2 = urllib2.urlopen(url)
print response2.getcode()
print len(response2.read())

print "第三种方法"
cj = cookielib.CookieJar()
opener = urllib2.build_opener(urllib2.HTTPCookieProcessor(cj))
urllib2.install_opener(opener)
response3 = urllib2.urlopen(url)
print response3.getcode()
print cj
print len(response3.read())