urllib/urllib2/httplib/httplib2区别:
http://hustcalm.me/blog/2013/11/14/httplib-httplib2-urllib-urllib2-whats-the-difference/
httplib2的使用方法:
http://blog.csdn.net/five3/article/details/7079140
httplib2 google:
http://httplib2.googlecode.com/hg/doc/html/libhttplib2.html