http://www.runoob.com/w3cnote/google-python-styleguide.html
https://www.douban.com/group/topic/101184966/
https://www.python.org/dev/peps/pep-0397/
https://docs.python.org/3/using/windows.html
http://blog.csdn.net/MrLevo520/article/details/69155636
http://blog.sae.sina.com.cn/archives/4781
https://www.cnblogs.com/Sherry-Queen/p/7173168.html
https://www.jianshu.com/p/768640d0bee6
http://www.runoob.com/csharp/csharp-type-conversion.html
