# Background Tasks - `BackgroundTasks`

You can declare a parameter in a *path operation function* or dependency function with the type `BackgroundTasks`, and then you can use it to schedule the execution of background tasks after the response is sent.

You can import it directly from `fastapi`:

```python
from fastapi import BackgroundTasks
```

        // The stats array in NodeStatusResponse contains everything after names
        // MAC is at index 0-5, actual stats at 6-11
        byte[] expectedStats = new byte[12];
        System.arraycopy(testMac, 0, expectedStats, 0, 6); // MAC at beginning
        System.arraycopy(stats, 0, expectedStats, 6, 6); // Stats after MAC
        assertArrayEquals(expectedStats, parsedStats);
    }

    @Test

    /**
     * Creates a new related content item.
     *
     * @param form the create form containing the new item data
     * @return HTML response redirecting to the list page after creation
     */
    @Execute
    @Secured({ ROLE })
    public HtmlResponse create(final CreateForm form) {
        verifyCrudMode(form.crudMode, CrudMode.CREATE, this::asListHtml);

     *
     * @return The type of data, must not be {@code null}.
     */
    Class<T> getType();

    /**
     * Creates a copy of the data suitable for storage in the cache. The original data to store can be mutated after the
     * cache is populated but the state of the cache must not change so we need to make a copy.
     *
     * @param data The data to store in the cache, must not be {@code null}.

	mu sync.Mutex // guards Close and Write
	fw *flate.Writer
}

func (w *pooledFlateWriter) Write(p []byte) (n int, err error) {
	w.mu.Lock()
	defer w.mu.Unlock()
	if w.fw == nil {
		return 0, errors.New("Write after Close")
	}
	return w.fw.Write(p)
}

func (w *pooledFlateWriter) Close() error {
	w.mu.Lock()
	defer w.mu.Unlock()
	var err error
	if w.fw != nil {
		err = w.fw.Close()
		flateWriterPool.Put(w.fw)

 *
 * <p>
 * This class defines the contract for delaying the crawling process at various points, such as:
 * </p>
 * <ul>
 *   <li>Before processing a URL ({@link #delayBeforeProcessing()})</li>
 *   <li>After processing a URL ({@link #delayAfterProcessing()})</li>
 *   <li>When there are no URLs in the queue ({@link #delayAtNoUrlInQueue()})</li>

			t.Errorf("Test %d: %s: mismatch number of objects after delete, expected = %v, found = %v", i+1, instanceType, testCase.objectsAfterDelete, result.Objects)
			continue
		}

		for idx := range result.Objects {
			if result.Objects[idx].Name != testCase.objectsAfterDelete[idx] {
				t.Errorf("Test %d: %s: Unexpected object found after delete, found = `%v`", i+1, instanceType, result.Objects[idx].Name)
			}
		}

        }

        // Assert: bytes before and after region remain unchanged.
        for (int i = 0; i < dstIndex; i++) {
            assertEquals((byte) 0x55, dst[i], "Unexpected change before copy region at " + i);
        }
        for (int i = dstIndex + len; i < dst.length; i++) {
            assertEquals((byte) 0x55, dst[i], "Unexpected change after copy region at " + i);
        }
    }

    @Test

./mc ls -r --versions myminio2/testbucket >/tmp/myminio2.txt

out=$(diff -qpruN /tmp/myminio1.txt /tmp/myminio2.txt)
ret=$?
if [ $ret -ne 0 ]; then
	echo "BUG: expected no missing entries after replication: $out"
	exit 1
fi

./mc rm myminio1/testbucket/dir/file
sleep 1s

./mc ls -r --versions myminio1/testbucket >/tmp/myminio1.txt
./mc ls -r --versions myminio2/testbucket >/tmp/myminio2.txt

   */
  @GwtIncompatible
  @J2ktIncompatible
  @CanIgnoreReturnValue
  @IgnoreJRERequirement // TODO: b/288085449 - Remove this once we use library-desugaring scents.
  @Beta // TODO: b/288085449 - Remove @Beta after we're sure that Java 8 APIs are safe for Android
  public FakeTicker advance(Duration duration) {
    return advance(duration.toNanos());
  }

  /**
   * Sets the increment applied to the ticker whenever it is queried.