En este caso, la función de tarea escribirá en un archivo (simulando el envío de un email).

Y como la operación de escritura no usa `async` y `await`, definimos la función con un `def` normal:

{* ../../docs_src/background_tasks/tutorial001_py310.py hl[6:9] *}

## Agregar la tarea en segundo plano { #add-the-background-task }

{* ../../docs_src/app_testing/tutorial001_py310.py hl[2,12,15:18] *}

/// tip | İpucu

Test fonksiyonlarının `async def` değil, normal `def` olduğuna dikkat edin.

Client'a yapılan çağrılar da `await` kullanılmadan, normal çağrılardır.

Bu sayede `pytest`'i ek bir karmaşıklık olmadan doğrudan kullanabilirsiniz.

///

/// note | Teknik Detaylar

   同样，你可以将 `dataclasses` 与标准类型注解组合使用。
8. 注意，这个 *路径操作函数* 使用的是常规的 `def` 而不是 `async def`。

   一如既往，在 FastAPI 中你可以按需组合 `def` 和 `async def`。

   如果需要回顾何时用哪一个，请查看关于 [`async` 和 `await`](../async.md#in-a-hurry) 的文档中的 _“急不可待？”_ 一节。
9. 这个 *路径操作函数* 返回的不是数据类（当然也可以返回数据类），而是包含内部数据的字典列表。

   FastAPI 会使用（包含数据类的）`response_model` 参数来转换响应。

你可以将 `dataclasses` 与其它类型注解以多种不同方式组合，来构建复杂的数据结构。

更多细节请参考上面代码中的内联注释提示。

        token_url, data=data, verify=False,
        allow_redirects=False, auth=(client_id, client_secret))

    print('body: ' + id_token_response.text)

    # we can now use the id_token as much as we want to access protected resources.
    tokens = json.loads(id_token_response.text)
    id_token = tokens['id_token']

    response = sts_client.assume_role_with_web_identity(

      return DELEGATE.next(value);
    }

    @Override
    public Integer previous(Integer value) {
      return DELEGATE.previous(value);
    }

    // Do *not* override offset() to delegate: We want to test the default implementation.

    @Override
    public long distance(Integer start, Integer end) {
      return DELEGATE.distance(start, end);
    }

    @Override
    public Integer minValue() {

				t.Fatalf("unable to write previously parsed content: %s", err)
			}
		}
		if err := w.Close(); err != nil {
			t.Fatalf("Unable to write archive: %s", err)
		}

		// TODO: We may want to check if the archive roundtrips. This would require
		// taking into account addition of the two zero trailer blocks that Writer.Close
		// appends.
	})

   * necessary. No observable state associated with this cache is modified until loading completes.
   *
   * <p>If another call to {@link #get} or {@link #getUnchecked} is currently loading the value for
   * {@code key}, simply waits for that thread to finish and returns its loaded value. Note that
   * multiple threads can concurrently load values for distinct keys.
   *

with open("file.txt") as file:
    file.read()
```

In neueren Versionen von Python gibt es auch einen **asynchronen Kontextmanager**. Sie würden ihn mit `async with` verwenden:

```Python
async with lifespan(app):
    await do_stuff()
```

# FastAPI dans des conteneurs - Docker { #fastapi-in-containers-docker }

Lors du déploiement d'applications FastAPI, une approche courante consiste à construire une **image de conteneur Linux**. C'est généralement fait avec [**Docker**](https://www.docker.com/). Vous pouvez ensuite déployer cette image de conteneur de plusieurs façons possibles.

import gradlebuild.testcleanup.extension.TestFileCleanUpExtension
import org.gradle.kotlin.dsl.support.serviceOf

/**
 * When run from a Continuous Integration environment, we only want to archive a subset of reports, mostly for
 * failing tasks only, to not use up unnecessary disk space on Team City. This also improves the performance of