python 3.X版本是不需要安装：urllib2包的，urllib和urllib2包集合成在一个包了
那现在问题是：
在python3.x版本中，如何使用：urllib2.urlopen()？
答：
import urllib.request
resp=urllib.request.urlopen(http://www.baidu.com)
来源：https://www.cnblogs.com/zdlfb/p/6130724.html
附：
Python2 urllib2 与 Python3 urllib.request API对照
| python2 | python3 |
|---|---|
| urllib2.urlopen() | urllib.request.urlopen() |
| urllib2.install_opener() | urllib.request.install_opener() |
| urllib2.build_opener() | urllib.request.build_opener() |
| urllib2.URLError | urllib.error.URLError |
| urllib2.HTTPError | urllib.error.HTTPError |
| urllib2.Request | urllib.request.Request |
| urllib2.OpenerDirector | urllib.request.OpenerDirector |
| urllib2.BaseHandler | urllib.request.BaseHandler |
| urllib2.HTTPDefaultErrorHandler | urllib.request.HTTPDefaultErrorHandler |
| urllib2.HTTPRedirectHandler | urllib.request.HTTPRedirectHandler |
| urllib2.HTTPCookieProcessor | urllib.request.HTTPCookieProcessor |
| urllib2.ProxyHandler | urllib.request.ProxyHandler |
| urllib2.HTTPPasswordMgr | urllib.request.HTTPPasswordMgr |
| urllib2.HTTPPasswordMgrWithDefaultRealm | urllib.request.HTTPPasswordMgrWithDefaultRealm |
| urllib2.AbstractBasicAuthHandler | urllib.request.AbstractBasicAuthHandler |
| urllib2.HTTPBasicAuthHandler | urllib.request.HTTPBasicAuthHandler |
| urllib2.ProxyBasicAuthHandler | urllib.request.ProxyBasicAuthHandler |
| urllib2.AbstractDigestAuthHandler | urllib.request.AbstractDigestAuthHandler |
| urllib2.HTTPDigestAuthHandler | urllib.request.HTTPDigestAuthHandler |
| urllib2.ProxyDigestAuthHandler | urllib.request.ProxyDigestAuthHandler |
| urllib2.HTTPHandler | urllib.request.HTTPHandler |
| urllib2.HTTPSHandler | urllib.request.HTTPSHandler |
| urllib2.FileHandler | urllib.request.FileHandler |
| urllib2.FTPHandler | urllib.request.FTPHandler |
| urllib2.CacheFTPHandler | urllib.request.CacheFTPHandler |
| urllib2.UnknownHandler | urllib.request.UnknownHandler |