* PR [#63](https://github.com/tiangolo/fastapi/pull/63).

## 0.6.4

* Add [technical details about `async def` handling to docs](https://fastapi.tiangolo.com/async/#very-technical-details). PR [#61](https://github.com/tiangolo/fastapi/pull/61).

    ```

=== "Python 3.9+"

    ```Python hl_lines="62-65"
    {!> ../../../docs_src/security/tutorial005_an_py39.py!}
    ```

=== "Python 3.8+"

    ```Python hl_lines="63-66"
    {!> ../../../docs_src/security/tutorial005_an.py!}
    ```

=== "Python 3.10+ nicht annotiert"

    !!! tip "Tipp"
        Bevorzugen Sie die `Annotated`-Version, falls möglich.

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