Most of these settings are variable (can change), like database URLs. And many could be sensitive, like secrets.

For this reason it's common to provide them in environment variables that are read by the application.

/// tip

To understand environment variables you can read [Environment Variables](../environment-variables.md).

///

## Types and validation { #types-and-validation }

//// tab | Python 3.10+

```Python
commons: Annotated[CommonQueryParams, Depends(CommonQueryParams)]
```

////

//// tab | Python 3.10+ non-Annotated

/// tip

Prefer to use the `Annotated` version if possible.

///

```Python
commons: CommonQueryParams = Depends(CommonQueryParams)
```

////

The last `CommonQueryParams`, in:

/// tip

You would normally do this **once**, right after you create the virtual environment.

///

Make sure the virtual environment is active (with the command above) and then run:

<div class="termy">

```console
$ python -m pip install --upgrade pip

---> 100%
```

</div>

/// tip

</div>

## In Detail { #in-detail }

The marker `@pytest.mark.anyio` tells pytest that this test function should be called asynchronously:

{* ../../docs_src/async_tests/app_a_py310/test_main.py hl[7] *}

/// tip

Note that the test function is now `async def` instead of just `def` as before when using the `TestClient`.

///

Then we can create an `AsyncClient` with the app, and send async requests to it, using `await`.

- path operation: path operation (do not translate)

### `///` admonitions

1) Keep the admonition keyword in English (do not translate `note`, `tip`, etc.).
2) If a title is present, prefer these canonical titles:

- `/// note | 備考`
- `/// note | 技術詳細`
- `/// tip | 豆知識`
- `/// warning | 注意`
- `/// info | 情報`
- `/// check | 確認`

/// tip | 팁

점(`.`)으로 시작하는 파일은 Linux, macOS 같은 Unix 계열 시스템에서 숨김 파일입니다.

하지만 dotenv 파일이 꼭 그 정확한 파일명을 가져야 하는 것은 아닙니다.

///

Pydantic은 외부 라이브러리를 사용해 이런 유형의 파일에서 읽는 기능을 지원합니다. 자세한 내용은 [Pydantic Settings: Dotenv (.env) 지원](https://docs.pydantic.dev/latest/concepts/pydantic_settings/#dotenv-env-support)을 참고하세요.

/// tip | 팁

이를 사용하려면 `pip install python-dotenv`가 필요합니다.

//// tab | Python 3.10+ 非 Annotated

/// tip

如有可能，優先使用 `Annotated` 版本。

///

```Python
commons: CommonQueryParams = Depends(CommonQueryParams)
```

////

...而是改為：

//// tab | Python 3.10+

```Python
commons: Annotated[CommonQueryParams, Depends()]
```

////

//// tab | Python 3.10+ 非 Annotated

/// tip

如有可能，優先使用 `Annotated` 版本。

///

这种做法非常常见：这些环境变量通常放在名为 `.env` 的文件中，该文件被称为 “dotenv”。

/// tip | 提示

以点（`.`）开头的文件在类 Unix 系统（如 Linux 和 macOS）中是隐藏文件。

但 dotenv 文件并不一定必须是这个确切的文件名。

///

Pydantic 支持使用一个外部库来从这类文件中读取。你可以在 [Pydantic Settings：Dotenv（.env）支持](https://docs.pydantic.dev/latest/concepts/pydantic_settings/#dotenv-env-support) 中阅读更多信息。

/// tip | 提示

要使其工作，你需要执行 `pip install python-dotenv`。

///

- app: 애플리케이션
- command: 명령어
- burger: 햄버거 (NOT 버거)

### `///` admonitions

1) Keep the admonition keyword in English (do not translate `note`, `tip`, etc.).
2) If a title is present, prefer these canonical titles:

- `/// note | 참고`
- `/// tip | 팁`
- `/// warning | 경고`
- `/// info | 정보`
- `/// danger | 위험`
- `/// note Technical Details | 기술 세부사항`
- `/// check | 확인`
Notes:

////

## `pip` をアップグレードする { #upgrade-pip }

/// tip | 豆知識

もし [`uv`](https://github.com/astral-sh/uv) を使用している場合は、 `pip` の代わりに `uv` を使ってインストールを行うため、 `pip` をアップグレードする必要はありません 😎。

///

もしパッケージのインストールに `pip`（Pythonに標準で付属しています）を使用しているなら、 `pip` を最新バージョンに**アップグレード**しましょう。

パッケージのインストール中に発生する想定外のエラーの多くは、最初に `pip` をアップグレードしておくだけで解決されます。

/// tip | 豆知識

通常、これは仮想環境を作成した直後に**一度だけ**実行します。

///