python中__name__

if __name__=="__main()":
允许这个程序在独立运行的时候做些有用的事情，不会在别的程序将它做为模块使用而引起冲突，也防止别人引用该模块执行其中的代码

看例子：

def test():
    print 'test is running!'
    if __name__=='__main__':
        print 'main is working'
    if __name__=='snail':
        print 'snail is working'

 

F5：

>>> test()
test is running!
main is working
>>> import snail
>>> snail.__name__
'snail'
>>> test()
test is running!
main is working
>>> snail.test()
test is running!
snail is working
>>>