class VLine(Line):
    def __getattribute__(self, name):
        if name == 'right':
            return self.left
        return super(VLine, self).__getattribute__(name)


class HLine(Line):
    def __getattribute__(self, name):
        if name == 'bottom':
            return self.top
        return super(HLine, self).__getattribute__(name)