# InputType

> **Class** in `langchain_classic`

📖 [View in docs](https://reference.langchain.com/python/langchain-classic/chains/conversational_retrieval/base/InputType)

Input type for ConversationalRetrievalChain.

## Signature

```python
InputType()
```

## Extends

- `BaseModel`

## Properties

- `question`
- `chat_history`

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[View source on GitHub](https://github.com/langchain-ai/langchain/blob/34489d61433cbf5044a630de2e7797e361672900/libs/langchain/langchain_classic/chains/conversational_retrieval/base.py#L68)