class Screen(object):

    @property

    def width(self):

        return self._width

    @width.setter

    def width(self,value):

        self._width=value

    @property

    def height(self):

        return self._height

    @height.setter

    def height(self,value):

        self._height=value

    @property

    def resolution(self):

        return self._width*self._height

s = Screen()

s.width = 1024

s.height = 768

print('resolution =', s.resolution)

if s.resolution == 786432:

    print('测试通过!')

else:

    print('测试失败!')