-- coding: utf-8 --

class Screen(object):

@property
def width(self):
    return self._width
@property
def height(self):
    return self._height
@width.setter
def width(self, w):
    if not isinstance(w, int):
        raise ValueError('width must be an integer!')
    self._width = w
@height.setter
def height(self, h):
    if not isinstance(h, int):
        raise ValueError('height must be an integer!')
    self._height = h

@property
def resolution(self):
    return self._width * self._height

大家应该都是这么写的吧