class Point(object): def __init__(self, x=0.0, y=0.0): self.x = x self.y = y def __repr__(self): return '' % (id(self), self.x, self.y) class Circle(Point): def __init__(self, x=0.0, y=0.0, radius=1.0): Point.__init__(self, x, y) self.radius = radius def __repr__(self): return '' % ( id(self), self.x, self.y, self.radius)