推荐使用顺序: machanize requests urllib和urllib2 httplib

http://www.bkjia.com/Pythonjc/994340.html
http://python.jobbole.com/84722/

requests

http://www.jb51.net/article/82048.htm

urllib和urllib2

http://www.jb51.net/article/65279.htm

http://linushai.blog.51cto.com/4976486/1344080

http://www.cnblogs.com/tiredoy/p/urllib_urllib2.html

http://www.pythontab.com/html/2014/pythonhexinbiancheng_1128/928.html

httlib

http://python.jobbole.com/81542/

cookielib

http://www.cnblogs.com/sysu-blackbear/p/3629770.html
https://docs.python.org/2/library/cookielib.html
http://www.cnblogs.com/isuifeng/p/5903116.html
http://www.jb51.net/article/63759.htm