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# SKActionTimingFunction

The signature for the custom timing block.

```
typealias SKActionTimingFunction = (Float) -> Float
```

## Discussion

The block parameters are defined as follows:

- `time`: The input time, where `0.0` represents the start time of the animation and `1.0` represents the end time of the animation.

The input value will be a value between `0.0` and `1.0`, inclusive. The block must also return a value between `0.0` and `1.0`. When the input time is `0.0`, the output value should be `0.0`. When the input time is `1.0`, the output value should also be `1.0`.

---

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