# coding: utf-8def login(func):    print("the first level")    def inner1(*args):        print("the second level")        def inner2(*args):            print("the third level")            def inner3(*args):                print("the forth level")                func(*args)            func(*args)            return inner3        func(*args)        return inner2    return inner1@logindef tv(name,password):    print("Welcome [%s] [%s] to TV page" % (name,password) )print(tv)tv = login(tv)print(tv)tv = tv("zhou","123")print(tv)tv = tv("zhouding","123456")print(tv)tv("zhoudingzhao","12345678")

　　执行结果如下：

the first level

<function login.<locals>.inner1 at 0x02D94150>

the first level

<function login.<locals>.inner1 at 0x02D94198>

the second level

the second level

Welcome [zhou] [123] to TV page

<function login.<locals>.inner1.<locals>.inner2 at 0x02D941E0>

the third level

the second level

Welcome [zhouding] [123456] to TV page

<function login.<locals>.inner1.<locals>.inner2.<locals>.inner3 at 0x02D94198>

the forth level

the second level

Welcome [zhoudingzhao] [12345678] to TV page

 

@login 的作用：相当于 tv = login(tv) ,把 tv 函数的内存地址传给login的参数 func ，login 函数返回其内部函数 inner1 的内存地址 给 tv 。当执行 tv 函数 的时候，其实是执行了login的 inner1 函数。