```Python hl_lines="3"
import os

name = os.getenv("MY_NAME", "World")
print(f"Hello {name} from Python")
```

/// tip

<a href="https://docs.python.org/3.8/library/os.html#os.getenv" class="external-link" target="_blank">`os.getenv()`</a> 的第二个参数是要返回的默认值。

如果没有提供默认值，默认为 `None`，此处我们提供了 `"World"` 作为要使用的默认值。

///

然后，您可以调用该 Python 程序：

<div class="termy">

```console
// 这里我们还没有设置环境变量
$ python main.py

![Swagger UI](https://fastapi.tiangolo.com/img/index/index-01-swagger-ui-simple.png)

### 他のAPIドキュメント

次に、<a href="http://127.0.0.1:8000/redoc" class="external-link" target="_blank">http://127.0.0.1:8000/redoc</a>にアクセスします。

先ほどとは異なる、自動生成された対話的APIドキュメントが表示されます (<a href="https://github.com/Rebilly/ReDoc" class="external-link" target="_blank">ReDoc</a>によって提供):

このため、**FastAPI**自体が代替のAPIドキュメントを提供します（ReDocを使用）。これは、 <a href="http://127.0.0.1:8000/redoc" class="external-link" target="_blank">http://127.0.0.1:8000/redoc</a> にアクセスすると確認できます。

<img src="/img/tutorial/path-params/image02.png">

同様に、互換性のあるツールが多数あります（多くの言語用のコード生成ツールを含む）。

## Pydantic

        String dfsSharePath = getDFSTestSharePath();

        String target = ( domain && !isStandalone() ) ? getTestDomain() : getTestServer();

        String path = link != null ? link : dfsSharePath + relative;

        if ( upper ) {
            dfsShare = dfsShare.toUpperCase(Locale.ROOT);
            path = path.toUpperCase(Locale.ROOT);
            target = target.toUpperCase(Locale.ROOT);
        }

```

/// info

Чтобы узнать больше о <a href="https://docs.pydantic.dev/" class="external-link" target="_blank">Pydantic, читайте его документацию</a>.

///

**FastAPI** целиком основан на Pydantic.

Вы увидите намного больше всего этого на практике в [Руководстве пользователя](tutorial/index.md){.internal-link target=_blank}.

## Аннотации типов в **FastAPI**

## Conclusion

Hiermee heb je basiskennis van wat **omgevingsvariabelen** zijn en hoe je ze in Python kunt gebruiken.

Je kunt er ook meer over lezen op de <a href="https://en.wikipedia.org/wiki/Environment_variable" class="external-link" target="_blank">Wikipedia over omgevingsvariabelen</a>.

## Conclusion

With this you should have a basic understanding of what **environment variables** are and how to use them in Python.

You can also read more about them in the <a href="https://en.wikipedia.org/wiki/Environment_variable" class="external-link" target="_blank">Wikipedia for Environment Variable</a>.

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        daemon --> worker2

        worker3["Worker process"]
        daemon --> worker3
    
```

These are all Java processes. Each process has a corresponding "runtime".
All source code in Gradle is written to target one or more of these runtimes.
Most source code targets the daemon and the remaining code either targets a single runtime, for example the Gradle client, or is shared across multiple runtimes.

## Composition by architecture modules

        File source = new File(new File(getBasedir(), getProjectsDirectory()), name);
        File target = new File(new File(getBasedir(), "target"), name);
        FileUtils.copyDirectoryStructureIfModified(source, target);
        return new File(target, "pom.xml");
    }

    protected MavenExecutionRequest createMavenExecutionRequest(File pom) throws Exception {