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# nemoguardrails.singleton

The singleton metaclass for ensuring only one instance of a class.

## Module Contents

### Classes

| Name                                               | Description                                                    |
| -------------------------------------------------- | -------------------------------------------------------------- |
| [`Singleton`](#nemoguardrails-singleton-Singleton) | Singleton metaclass for ensuring only one instance of a class. |

### API

```python
class nemoguardrails.singleton.Singleton()
```

Abstract

**Bases:** `ABCMeta`, `type`

Singleton metaclass for ensuring only one instance of a class.

```python
nemoguardrails.singleton.Singleton.__call__(
    args = (),
    kwargs = {}
)
```

Call method for the singleton metaclass.