A maioria dessas configurações é variável (pode mudar), como URLs de banco de dados. E muitas podem ser sensíveis, como segredos.

Por esse motivo, é comum fornecê-las em variáveis de ambiente lidas pela aplicação.

/// tip | Dica

Para entender variáveis de ambiente, você pode ler [Variáveis de Ambiente](../environment-variables.md){.internal-link target=_blank}.

///

## Tipagem e validação { #types-and-validation }

addAttachmentClass(attachment) {\n    $(this.getTipElement()).addClass(`${CLASS_PREFIX}-${attachment}`)\n  }\n\n  getTipElement() {\n    this.tip = this.tip || $(this.config.template)[0]\n    return this.tip\n  }\n\n  setContent() {\n    const tip = this.getTipElement()\n    this.setElementContent($(tip.querySelectorAll(SELECTOR_TOOLTIP_INNER)), this.getTitle())\n    $(tip).removeClass(`${CLASS_NAME_FADE} ${CLASS_NAME_SHOW}`)\n  }\n\n  setElementContent($element, content) {\n    if (typeof content === 'object'...

</blockquote>

## Araştırma

Önceki alternatifleri kullanarak hepsinden bir şeyler öğrenip, fikirler alıp, bunları kendim ve çalıştığım geliştirici ekipler için en iyi şekilde birleştirebilme şansım oldu.

Mesela, ideal olarak standart Python tip belirteçlerine dayanması gerektiği açıktı.

//// tab | Python 3.9+

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

////

//// tab | Python 3.9+ non-Annotated

/// tip

Prefer to use the `Annotated` version if possible.

///

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

////

The last `CommonQueryParams`, in:

//// tab | Python 3.9+

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

////

//// tab | Python 3.9+ non-Annotated

/// tip | Dica

Utilize a versão com `Annotated` se possível.

///

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

////

O último `CommonQueryParams`, em:

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){.internal-link target=_blank}.

///

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

Эта часть вполне обычна, большая часть кода вам уже знакома:

{* ../../docs_src/openapi_callbacks/tutorial001_py310.py hl[7:11,34:51] *}

/// tip | Совет

Query-параметр `callback_url` использует тип Pydantic <a href="https://docs.pydantic.dev/latest/api/networks/" class="external-link" target="_blank">Url</a>.

///

```

</div>

////

/// tip | 팁

가상 환경에 새로운 패키지를 설치할 때마다, 해당 환경을 다시 활성화하세요.

이렇게 하면 해당 패키지로 설치된 **터미널(<abbr title="command line interface">CLI</abbr>) 프로그램**을 사용할 때, 전역에 설치된 다른 버전이 아니라, 가상 환경 안에 설치된 정확한 버전을 사용합니다.

///

## 가상 환경이 활성화 여부 확인

가상 환경이 활성화되었는지 확인합니다. (이전 명령어가 제대로 작동했는지 확인합니다).

/// tip | 팁

这种做法相当常见，有一个名称，这些环境变量通常放在一个名为 `.env` 的文件中，该文件被称为“dotenv”。

/// tip

以点 (`.`) 开头的文件是 Unix-like 系统（如 Linux 和 macOS）中的隐藏文件。

但是，dotenv 文件实际上不一定要具有确切的文件名。

///

Pydantic 支持使用外部库从这些类型的文件中读取。您可以在<a href="https://docs.pydantic.dev/latest/concepts/pydantic_settings/#dotenv-env-support" class="external-link" target="_blank">Pydantic 设置: Dotenv (.env) 支持</a>中阅读更多相关信息。

/// tip

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

///

/// 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