# is_type_alias_type

> **Function** in `langsmith`

📖 [View in docs](https://reference.langchain.com/python/langsmith/_openapi_client/_utils/_typing/is_type_alias_type)

Return whether the provided argument is an instance of `TypeAliasType`.

```python
type Int = int
is_type_alias_type(Int)
# > True
Str = TypeAliasType("Str", str)
is_type_alias_type(Str)
# > True
```

## Signature

```python
is_type_alias_type(
    tp: Any,
    /,
) -> TypeIs[typing_extensions.TypeAliasType]
```

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[View source on GitHub](https://github.com/langchain-ai/langsmith-sdk/blob/d6cd6082f09e7826a2d6afe444ae6119e61b82a6/python/langsmith/_openapi_client/_utils/_typing.py#L59)