# 先回顾一下
class Room:
    def __init__(self,name,width,length):
        self.name = name
        self.width = width
        self.length = length
    @property
    def area(self):
        return self.width * self.length
r1 = Room('wang',100,100)
print(r1.area)

class Lazyproperty:
    def __init__(self,func):
        self.func = func
    def __get__(self,instance,owner):
        print("我们自己定义的属性")
        if instance is None:
            return self
        return self.func(instance)
class Room:
    def __init__(self,name,width,length):
        self.name = name
        self.width = width
        self.length = length
    @Lazyproperty
    # area = Lazyproperty(area)
    # 现在area是一个类，而不是函数
    def area(self):
        # print(self.area)
        return self.width * self.length
r1=Room('alex',1,1)
print(r1.area)