nonlocal的使用

nonlocal：用来声明外层的局部变量

global：用来声明全局变量

 1 a = 100
 2 
 3 def outer():
 4     b = 10
 5     def inner():
 6         nonlocal b
 7         print("inner b:",b)
 8         b=20
 9 
10         global a
11         a = 1000
12         print("b:",b)
13 
14     inner()
15     print("outer b:",b)
16 
17 outer()
18 print("a:",a)