for (int i = 0; i < threadCount; i++) {
            final int index = i;
            new Thread(() -> {
                try {
                    startLatch.await();

                    if (index % 3 == 0) {
                        // Some threads wipe password
                        auth.secureWipePassword();
                    } else if (index % 3 == 1) {

    // (which will block) in the same thread.
    new Thread() {
      @Override
      public void run() {
        inputFuture.set(SLOW_FUNC_VALID_INPUT_DATA);
      }
    }.start();
    funcIsWaitingLatch.await();

    assertTrue(resultFuture.cancel(true));
    assertTrue(resultFuture.isCancelled());
    assertFalse(inputFuture.isCancelled());
    assertFalse(outputFuture.isCancelled());

    // (which will block) in the same thread.
    new Thread() {
      @Override
      public void run() {
        inputFuture.set(SLOW_FUNC_VALID_INPUT_DATA);
      }
    }.start();
    funcIsWaitingLatch.await();

    assertTrue(resultFuture.cancel(true));
    assertTrue(resultFuture.isCancelled());
    assertFalse(inputFuture.isCancelled());
    assertFalse(outputFuture.isCancelled());

      lock.lock();
      try {
        locked.countDown();
        finishLatch.await(1, MINUTES);
      } catch (InterruptedException e) {
        fail(e.toString());
      } finally {
        lock.unlock();
      }
    }

    void waitUntilHoldingLock() throws InterruptedException {
      locked.await(1, MINUTES);
    }

    void releaseLockAndFinish() throws InterruptedException {

      lock.lock();
      try {
        locked.countDown();
        finishLatch.await(1, MINUTES);
      } catch (InterruptedException e) {
        fail(e.toString());
      } finally {
        lock.unlock();
      }
    }

    void waitUntilHoldingLock() throws InterruptedException {
      locked.await(1, MINUTES);
    }

    void releaseLockAndFinish() throws InterruptedException {

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.py hl[6:9] *}

## Agregar la tarea en segundo plano

Pour ces cas, vous pouvez spécifier un appel à `jsonable_encoder` pour convertir vos données avant de les passer à une réponse :

{* ../../docs_src/response_directly/tutorial001.py hl[6:7,21:22] *}

/// note | Détails techniques

Vous pouvez aussi utiliser `from starlette.responses import JSONResponse`.

## ✍ 📋 🔢

✍ 🔢 🏃 🖥 📋.

⚫️ 🐩 🔢 👈 💪 📨 🔢.

⚫️ 💪 `async def` ⚖️ 😐 `def` 🔢, **FastAPI** 🔜 💭 ❔ 🍵 ⚫️ ☑.

👉 💼, 📋 🔢 🔜 ✍ 📁 (⚖ 📨 📧).

& ✍ 🛠️ 🚫 ⚙️ `async` & `await`, 👥 🔬 🔢 ⏮️ 😐 `def`:

{* ../../docs_src/background_tasks/tutorial001.py hl[6:9] *}

## 🚮 🖥 📋

🔘 👆 *➡ 🛠️ 🔢*, 🚶‍♀️ 👆 📋 🔢 *🖥 📋* 🎚 ⏮️ 👩‍🔬 `.add_task()`:

        doneSignal.countDown();
      }
    }.start();

    try {
      computingSignal.await();
    } catch (InterruptedException e) {
      throw new RuntimeException(e);
    }

    map.put(one, two);
    assertSame(two, map.get(one));
    startSignal.countDown();

    try {
      doneSignal.await();
    } catch (InterruptedException e) {
      throw new RuntimeException(e);
    }

      Producer producer = new Producer(q, 1);
      // producing one, will ask for two
      Future<?> producerThread = threadPool.submit(producer);
      producer.beganProducing.await();

      // make sure we time out
      Stopwatch timer = Stopwatch.createStarted();

      int drained = drain(q, new ArrayList<>(), 2, 10, MILLISECONDS, interruptibly);
      assertThat(drained).isAtMost(1);