如何使 cocos2d 精灵每秒缩放（以获得脉动效果）？

我想让精灵每秒缩放一次，使其看起来像是鼓起来并脉动。我怎样才能做到这一点？

由于之前的帖子包含语法错误。更准确地说，我发布了工作代码：

CCSprite * sprite = ...; // create the sprite.
id scaleUpAction =  [CCEaseInOut actionWithAction:[CCScaleTo actionWithDuration:1 scaleX:1.0 scaleY:1.0] rate:2.0];
id scaleDownAction = [CCEaseInOut actionWithAction:[CCScaleTo actionWithDuration:0.5 scaleX:0.8 scaleY:0.8] rate:2.0];
CCSequence *scaleSeq = [CCSequence actions:scaleUpAction, scaleDownAction, nil];
[sprite runAction:[CCRepeatForever actionWithAction:scaleSeq]];