说明：  这个通过例子学python的资料，是从一个python学习的网站上下下来的，通过一个个编程实例来学习python，我认为这是学习python一个非常高效的途径。
(Learn python this information by example, learning from a web site up and down down the python, and through a months programming examples to learn python, I think this is a very efficient learning python way.)