#圆形类
class Circle:
    def __init__(self,radius):
        self.radius = radius

    def area(self):
        '面积'
        return self.radius **2  * 3.14

    def perimeter(self):
        '周长'
        return self.radius * 2 *3.14

圆 = Circle(8)
print(圆.area())
print(圆.perimeter())