# callback

> **Function** in `langchain_classic`

📖 [View in docs](https://reference.langchain.com/python/langchain-classic/callbacks/tracers/logging/LoggingCallbackHandler/__init__/callback)

## Signature

```python
callback(
    text: str,
) -> None
```

---

[View source on GitHub](https://github.com/langchain-ai/langchain/blob/185119f98e6286253a2326d7cf4f59592678023d/libs/langchain/langchain_classic/callbacks/tracers/logging.py#L35)