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    img: https://fastapi.tiangolo.com/img/sponsors/databento.svg

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

Wenn Sie wie oben einen Kontextmanager oder einen asynchronen Kontextmanager erstellen, führt dieser vor dem Betreten des `with`-Blocks den Code vor dem `yield` aus, und nach dem Verlassen des `with`-Blocks wird er den Code nach dem `yield` ausführen.

In unserem obigen Codebeispiel verwenden wir ihn nicht direkt, sondern übergeben ihn an FastAPI, damit es ihn verwenden kann.

		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.
	})

 * strategies.
 *
 * <ul>
 *   <li>SafeAtomicHelper: uses Atomic FieldsUpdaters to implement synchronization
 *   <li>SynchronizedHelper: uses {@code synchronized} blocks for synchronization
 * </ul>
 *
 * To force selection of our fallback strategies we load {@link AggregateFutureState} (and all of
 * {@code com.google.common.util.concurrent}) in degenerate class loaders which make certain

     * uses 10 MiB).
     */
    const val DEFAULT_INITIAL_WINDOW_SIZE = 65535

    /** HTTP/2: Size in bytes of the table used to decode the sender's header blocks. */
    const val HEADER_TABLE_SIZE = 1

    /** HTTP/2: The peer must not send a PUSH_PROMISE frame when this is 0. */
    const val ENABLE_PUSH = 2

    /** Sender's maximum number of concurrent streams. */

  protected abstract <V> ListenableFuture<V> createListenableFuture(
      V value, @Nullable Exception except, CountDownLatch waitOn);

  /** Tests that the {@link Future#get()} method blocks until a value is available. */
  public void testGetBlocksUntilValueAvailable() throws Throwable {

    assertFalse(future.isDone());
    assertFalse(future.isCancelled());

	s := syscall.Statfs_t{}
	err = syscall.Statfs(path, &s)
	if err != nil {
		return Info{}, err
	}
	reservedBlocks := s.Bfree - s.Bavail
	info = Info{
		Total: uint64(s.Frsize) * (s.Blocks - reservedBlocks),
		Free:  uint64(s.Frsize) * s.Bavail,
		Files: s.Files,
		Ffree: s.Ffree,
		//nolint:unconvert
		FSType: getFSType(int64(s.Type)),
	}

	st := syscall.Stat_t{}
	err = syscall.Stat(path, &st)

    }

    BlockDoc getBlock(String name) {
        def block = classBlocks.find { it.name == name }
        if (block) {
            return block
        }
        for (extensionDoc in classExtensions) {
            block = extensionDoc.extensionBlocks.find { it.name == name }
            if (block) {
                return block
            }
        }

	s := syscall.Statfs_t{}
	err = syscall.Statfs(path, &s)
	if err != nil {
		return Info{}, err
	}
	reservedBlocks := s.Bfree - s.Bavail
	info = Info{
		Total:  uint64(s.Frsize) * (s.Blocks - reservedBlocks),
		Free:   uint64(s.Frsize) * s.Bavail,
		Files:  s.Files,
		Ffree:  s.Ffree,
		FSType: getFSType(s.Type),
	}
	// Check for overflows.
	// https://github.com/minio/minio/issues/8035

			return dst, io.EOF
		}
	}
	// Read until next line.
	in, err := r.buf.ReadBytes('\n')
	dst = append(dst, in...)
	return dst, err
}

// jsonSplitSize is the size of each block.
// Blocks will read this much and find the first following newline.
// 128KB appears to be a very reasonable default.
const jsonSplitSize = 128 << 10

// startReaders will read the header if needed and spin up a parser