inheritance and property in python

inheritance_property.py

class xy(object):
    """docstring for xy"""
    
    def __init__(self, x, y):
        self.x = x
        self.y = y
        
    @property
    def x(self):
        return self.__x

    @x.setter
    def x(self, x):
        if x < 0:
            self.__x = 0
        elif x > 1000:
            self.__x = 1000
        else:
            self.__x = x

    @property
    def y(self):
        return self.__y

    @y.setter
    def y(self, y):
        if y < 0:
            self.__y = 0
        elif y > 1000:
            self.__y = 1000
        else:
            self.__y = y

    def calculatexy(self):
        return self.__x + self.__y

class ClassCheck(xy):
    """docstring for ClassCheck"""
    def __init__(self, x, y, z):
        self.x = x
        self.y = y
        self.z = z

    @property
    def z(self):
        return self.__z

    @z.setter
    def z(self, z):
        if z < 0:
            self.__z = 0
        elif z > 1000:
            self.__z = 1000
        else:
            self.__z = z

    def calculatexyz(self):
        print self.calculatexy() + self.__z
        


if __name__ == '__main__':
    ctest = ClassCheck(10001, 1001,20)
    print(ctest.x,ctest.y,ctest.z)
    ctest.calculatexy()
    ctest.calculatexyz()