If you scroll back up on the printout or screen here, you'll see that you can actually not only declare function's prototypes, their general structure.

如果我回滚到打印输出或者这个屏幕，你们将看到你们不仅可以声明函数的原型,它们的一般结构。

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But the fact is it's a state function, in a general way.

事实上这也是个态函数，是普遍成立的。

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