python分别用python2和python3伪装浏览器爬取网页内容

#! /usr/bin/env python
# -*- coding=utf-8 -*-
# @Author python
import urllib.request
url = "http://www.baidu.com"
html = urllib.request.urlopen(url).read(）
print(html)

#! /usr/bin/env python
# -*- coding=utf-8 -*- 
# @Author python
import urllib2
url="http://www.baidu.com"
req_header = {'User-Agent':'Mozilla/5.0 (Windows NT 6.1) AppleWebKit/537.11 (KHTML, like Gecko) Chrome/23.0.1271.64 Safari/537.11',
             'Accept':'text/html;q=0.9,*/*;q=0.8',
             'Accept-Charset':'ISO-8859-1,utf-8;q=0.7,*;q=0.3',
             'Accept-Encoding':'gzip',
             'Connection':'close',
             'Referer':None #注意如果依然不能抓取的话，这里可以设置抓取网站的host
             }
req_timeout = 5
req = urllib2.Request(url,None,req_header)
resp = urllib2.urlopen(req,None,req_timeout)
html = resp.read()
print(html)

#! /usr/bin/env python
# -*- coding=utf-8 -*- 
# @Author python
import urllib.request
  
url = "http://www.baidu.com"
headers = {'User-Agent':'Mozilla/5.0 (Windows NT 6.1) AppleWebKit/537.11 (KHTML, like Gecko) Chrome/23.0.1271.64 Safari/537.11',
             'Accept':'text/html;q=0.9,*/*;q=0.8',
             'Accept-Charset':'ISO-8859-1,utf-8;q=0.7,*;q=0.3',
             'Accept-Encoding':'gzip',
             'Connection':'close',
             'Referer':None #注意如果依然不能抓取，这里可以设置抓取网站的host
             }
  
opener = urllib.request.build_opener()
opener.addheaders = [headers]
data = opener.open(url).read()
print(data)