Twenty-six of the nested function

Twenty-six of the nested function

A nested function definition

• Internal function defined functions can not be used outside the function. (Only one function that it belongs to or deeper call)

form cmath import pi # 3.14

def circle(r,action):
    if action == 'p':
        def perimeter():  #周长
            res = 2*pi*r
    elif action == 'a':
        def area():
            res = pi*r**2
    else:
        res = 'error'
    return res    

Second, the nested function calls

def max(x, y):
    if x > y:
        return x
    else:
        return y


def max1(a, b, c, d):
    res1 = max2(a, b)
    res2 = max2(res1, c)
    res3 = max2(res2, d)
    return res3

max1(20,59,100,0)