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# MLKey

An abstract base class for machine learning key types.

```
class MLKey
```

## Overview

You don’t create use this class directly. Instead, use a class that inherits from this one, such as [`MLParameterKey`](/documentation/CoreML/MLParameterKey) or [`MLMetricKey`](/documentation/CoreML/MLMetricKey).

## Topics

### Retrieving a key’s information

[`name`](/documentation/CoreML/MLKey/name)

The name of the machine learning key.

[`scope`](/documentation/CoreML/MLKey/scope)

The applicable scope of the machine learning key.


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