Python覆盖嵌套函数中的变量

在Python
3.x中，可以使用

nonlocal

def outer():    string = ""    def inner():        nonlocal string        string = "String was changed by a nested function!"    inner()    return string

在Python 2.x中，您可以使用带有单个元素的列表并覆盖该单个元素：

def outer():    string = [""]    def inner():        string[0] = "String was changed by a nested function!"    inner()    return string[0]