#coidng=utf-8
import math
class Circle(object):
    def __init__(self, radius):
        self.radius = radius
    @property
    def area(self):
        return math.pi*self.radius**2
    @property
    def perimeter(self):
        return 2*math.pi*self.radius
#coidng=utf-8
import math
class Circle(object):
    def __init__(self, radius):
        self.radius = radius
    @property
    def area(self):
        return math.pi*self.radius**2
    @property
    def perimeter(self):
        return 2*math.pi*self.radius
#coidng=utf-8