局部变量
def discount(price, rate):
final_price = price * rate
return final_price
old_price = float(input('请输入原价：')) 全局变量
rate = float(input('请输入折扣率：'))
new_price = discount(old_price, rate)
print('打折后的价格是：',new_price)
print('打印局部变量final_price的值：'，final_price) 显示为定义的变量，final_price为discount函数中的变量，为局部变量，出了discount就无效了
在局部变量中定义全局变量
>>> test1 = 5
>>> def change():
test1 = 10
print(test1)
>>> change()
10
>>> test1
5
>>> def change():
global test1
test1 = 10
print(test1)
>>> change()
10
>>> test1
10
内嵌函数
>>> def fun1():
print('fun1正在被调用..')
def fun2():
print('fun2正在被调用...')
fun2()
>>> fun1() 调用fun1()后执行调用fun2()
fun1正在被调用..
fun2正在被调用...
闭包 如果在一个内部函数里，对在外部作用域的变量进行引用
>>> def fun3(x):
def fun4(y):
return x * y
return fun4
>>> fun3(1)
<function fun3.<locals>.fun4 at 0x0000000002F549D8>
>>> type(fun3)
<class 'function'>
>>> fun3(1)(2)
2
>>> def fun1():
x = 5
def fun2():
x *= x
return x
return fun2()
>>> fun1()
Traceback (most recent call last):
File "<pyshell#52>", line 1, in <module>
fun1()
File "<pyshell#50>", line 6, in fun1
return fun2()
File "<pyshell#50>", line 4, in fun2
x *= x
UnboundLocalError: local variable 'x' referenced before assignment
>>> def fun1():
x = 5
def fun2():
nonlocal x 强制声明非局部变量
x *= x
return x
return fun2()
>>> fun1()
25
原文地址：http://blog.51cto.com/12686555/2135500