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# biometry(fallback:)

Creates a requirement that requires biometric authentication or a fallback requirement that you specify.

```
class func biometry(fallback: LABiometryFallbackRequirement) -> Self
```

## Parameters

`fallback`

A requirement to use a fallback if biometric authentication fails or is unavailable, or if the user prefers not to use biometric authentication.

## Return Value

Returns a requirement that requires biometric authentication or a fallback requirement that you specify.

## Discussion

---

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