Up to now, you have been using common data types, like:

* `int`
* `float`
* `str`
* `bool`

But you can also use more complex data types.

And you will still have the same features as seen up to now:

* Great editor support.
* Data conversion from incoming requests.
* Data conversion for response data.
* Data validation.
* Automatic annotation and documentation.

## Other data types

        "/items/plumbus?token=jessica", headers={"X-Token": "fake-super-secret-token"}
    )
    assert response.status_code == 200, response.text
    assert response.json() == {"item_id": "plumbus", "name": "The great Plumbus"}


def test_put_forbidden(client: TestClient):
    response = client.put(
        "/items/bar?token=jessica", headers={"X-Token": "fake-super-secret-token"}
    )

That means that any value read in Python from an environment variable will be a `str`, and any conversion to a different type or validation has to be done in code.

## Pydantic `Settings`

Fortunately, Pydantic provides a great utility to handle these settings coming from environment variables with <a href="https://docs.pydantic.dev/latest/usage/pydantic_settings/" class="external-link" target="_blank">Pydantic: Settings management</a>.

Peewee has some heavy assumptions about its defaults and about how it should be used.

If you are developing an application with an older non-async framework, and can work with all its defaults, **it can be a great tool**.

But if you need to change some of the defaults, support more than one predefined database, work with an async framework (like FastAPI), etc, you will need to add quite some complex extra code to override those defaults.

* **Fast to code**: Increase the speed to develop features by about 200% to 300%. *
* **Fewer bugs**: Reduce about 40% of human (developer) induced errors. *
* **Intuitive**: Great editor support. <abbr title="also known as auto-complete, autocompletion, IntelliSense">Completion</abbr> everywhere. Less time debugging.
* **Easy**: Designed to be easy to use and learn. Less time reading docs.

* **Fast to code**: Increase the speed to develop features by about 200% to 300%. *
* **Fewer bugs**: Reduce about 40% of human (developer) induced errors. *
* **Intuitive**: Great editor support. <abbr title="also known as auto-complete, autocompletion, IntelliSense">Completion</abbr> everywhere. Less time debugging.
* **Easy**: Designed to be easy to use and learn. Less time reading docs.

If you declare it as is, because it is a singular value, **FastAPI** will assume that it is a query parameter.

But you can instruct **FastAPI** to treat it as another body key using `Body`:

=== "Python 3.10+"

    ```Python hl_lines="23"
    {!> ../../../docs_src/body_multiple_params/tutorial003_an_py310.py!}
    ```

=== "Python 3.9+"