## `BackgroundTasks` の使用

まず初めに、`BackgroundTasks` をインポートし、` BackgroundTasks` の型宣言と共に、*path operation 関数* のパラメーターを定義します:

{* ../../docs_src/background_tasks/tutorial001.py hl[1,13] *}

**FastAPI** は、`BackgroundTasks` 型のオブジェクトを作成し、そのパラメーターに渡します。

## タスク関数の作成

バックグラウンドタスクとして実行される関数を作成します。

これは、パラメーターを受け取ることができる単なる標準的な関数です。

これは `async def` または通常の `def` 関数であり、**FastAPI** はこれを正しく処理します。

has-symbols@^1.0.3:
  version "1.0.3"
  resolved "https://registry.yarnpkg.com/has-symbols/-/has-symbols-1.0.3.tgz#bb7b2c4349251dce87b125f7bdf874aa7c8b39f8"
  integrity sha512-l3LCuF6MgDNwTDKkdYGEihYjt5pRPbEg46rtlmnSPlUbgmB8LOIrKJbYYFBSbnPaJexMKtiPO8hmeRjRz2Td+A==

has@^1.0.3:
  version "1.0.3"
  resolved "https://registry.yarnpkg.com/has/-/has-1.0.3.tgz#722d7cbfc1f6aa8241f16dd814e011e1f41e8796"

    assertThat(Doubles.contains(EMPTY, 1.0)).isFalse();
    assertThat(Doubles.contains(ARRAY1, 2.0)).isFalse();
    assertThat(Doubles.contains(ARRAY234, 1.0)).isFalse();
    assertThat(Doubles.contains(new double[] {-1.0}, -1.0)).isTrue();
    assertThat(Doubles.contains(ARRAY234, 2.0)).isTrue();
    assertThat(Doubles.contains(ARRAY234, 3.0)).isTrue();
    assertThat(Doubles.contains(ARRAY234, 4.0)).isTrue();

   * (10, ∞) => "baz"} then {@code rangeMap.subRangeMap(Range.open(3, 12))} would return a range map
   * with the entries {@code (3, 5] => "foo", (6, 8) => "bar", (10, 12) => "baz"}.
   *
   * <p>The returned range map supports all optional operations that this range map supports, except
   * for {@code asMapOfRanges().iterator().remove()}.
   *

        multimap.putAll("bar", asList(4, 5));
        multimap.putAll("foo", asList(6));
        multimap.putAll("baz", asList(7, 8));
        multimap.putAll("dog", asList(9));
        multimap.putAll("bar", asList(10, 11));
        multimap.putAll("cat", asList(12, 13, 14));
        return multimap.keySet().iterator();
      }

      @Override
      protected void verify(List<String> elements) {

  public void testManyEqual() {
    assertThat(
            ComparisonChain.start()
                .compare(1, 1)
                .compare(1L, 1L)
                .compareFalseFirst(true, true)
                .compare(1.0, 1.0)
                .compare(1.0f, 1.0f)
                .compare("a", "a", Ordering.usingToString())
                .result())
        .isEqualTo(0);
  }

  public void testShortCircuitLess() {
    assertThat(

First, import `BackgroundTasks` and define a parameter in your *path operation function* with a type declaration of `BackgroundTasks`:

{* ../../docs_src/background_tasks/tutorial001.py hl[1,13] *}

**FastAPI** will create the object of type `BackgroundTasks` for you and pass it as that parameter.

## Create a task function { #create-a-task-function }

Create a function to be run as the background task.

## Usando `BackgroundTasks`

Primeiro, importe `BackgroundTasks` e defina um parâmetro em sua _função de operação de caminho_ com uma declaração de tipo de `BackgroundTasks`:

{* ../../docs_src/background_tasks/tutorial001.py hl[1,13] *}

O **FastAPI** criará o objeto do tipo `BackgroundTasks` para você e o passará como esse parâmetro.

## Criar uma função de tarefa

Crie uma função a ser executada como tarefa em segundo plano.

Wie Sie sehen, ist die Funktion mit einem `@asynccontextmanager` versehen.

Dadurch wird die Funktion in einen sogenannten „**asynchronen Kontextmanager**“ umgewandelt.

{* ../../docs_src/events/tutorial003.py hl[1,13] *}

Ein **Kontextmanager** in Python ist etwas, das Sie in einer `with`-Anweisung verwenden können, zum Beispiel kann `open()` als Kontextmanager verwendet werden:

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

        // Heartbeat monitoring
        scheduler.scheduleAtFixedRate(this::checkHeartbeats, 30, 30, TimeUnit.SECONDS);

        // Registration monitoring
        scheduler.scheduleAtFixedRate(this::monitorRegistrations, 10, 10, TimeUnit.SECONDS);
    }

    /**
     * Registers for witness notifications.
     *
     * @param shareName the share name to monitor
     * @param serverAddress the server address