class Rectangle: def init(self, length, width): self.length = length self.width = width

def area(self):
    return self.length * self.width

def perimeter(self):
    return 2 * (self.length + self.width)

class Square(Rectangle): def init(self, side): super().init(side, side)

def area(self):
    return self.length ** 2

def perimeter(self):
    return 4 * self.length

使用对象调用

r = Rectangle(5, 3) print("矩形面积为：", r.area()) print("矩形周长为：", r.perimeter())

s = Square(4) print("正方形面积为：", s.area()) print("正方形周长为：", s.perimeter())