class Screen(object):

@property
def width(self):

return self._width

@property
def height(self):

return self._height

@width.setter
def width(self,value):

self._width=value

@height.setter
def height(self,value):

self._height=value

@property
def resolution(self):

return self._width*self._height

# 测试:
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!')