def METHOD_NAME(self):
    d = Dimension(3, 9)
    self.assertEquals(d.width, 3)
    self.assertEquals(d.height, 9)
    d.width = 42
    self.assertEquals(d.width, 42)
    self.assertEquals(d.height, 9)
    try:
        d.foo
    except AttributeError:
        pass
    else:
        raise AssertionError('d.foo should throw type error')