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# kSecTransformActionExternalizeExtraData

An action that triggers after data is stored.

```
let kSecTransformActionExternalizeExtraData: CFString
```

## Discussion

Allows for adding to the data that is stored using an override to the kSecTransformActionExternalizeExtraData block. The output of this override is a dictionary that contains the custom externalized data. A common use of this override is to write out a version number of a custom transform.

---

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