Future<?> scheduled = executorService.schedule(task, delay, timeUnit);
    /*
     * Even when the user interrupts the task, we pass `false` to `cancel` so that we don't
     * interrupt a second time after the interruption performed by TrustedListenableFutureTask.
     */
    task.addListener(() -> scheduled.cancel(false), directExecutor());
    return task;
  }

  /**

  }

  @Override
  public ListenableScheduledFuture<?> schedule(Runnable command, long delay, TimeUnit unit) {
    Preconditions.checkNotNull(command, "command must not be null");
    Preconditions.checkNotNull(unit, "unit must not be null!");
    return schedule(Executors.callable(command), delay, unit);
  }

  @Override
  public <V> ListenableScheduledFuture<V> schedule(
      Callable<V> callable, long delay, TimeUnit unit) {

  }

  @Override
  public ListenableScheduledFuture<?> schedule(Runnable command, long delay, TimeUnit unit) {
    Preconditions.checkNotNull(command, "command must not be null");
    Preconditions.checkNotNull(unit, "unit must not be null!");
    return schedule(Executors.callable(command), delay, unit);
  }

  @Override
  public <V> ListenableScheduledFuture<V> schedule(
      Callable<V> callable, long delay, TimeUnit unit) {

    return new NoOpScheduledExecutorService();
  }

  /**
   * Creates a scheduled executor service that runs each task in the thread that invokes {@code
   * execute/submit/schedule}, as in {@link CallerRunsPolicy}. This applies both to individually
   * submitted tasks and to collections of tasks submitted via {@code invokeAll}, {@code invokeAny},
   * {@code schedule}, {@code scheduleAtFixedRate}, and {@code scheduleWithFixedDelay}. In the case

    # https://github.com/sqlalchemy/sqlalchemy/commit/59521abcc0676e936b31a523bd968fc157fef0c2
    'ignore:datetime\.datetime\.utcfromtimestamp\(\) is deprecated and scheduled for removal in a future version\..*:DeprecationWarning:sqlalchemy',
    # Trio 24.1.0 raises a warning from attrs
    # Ref: https://github.com/python-trio/trio/pull/3054
    # Remove once there's a new version of Trio

   * This counter prevents an ABA issue where a thread may successfully schedule the worker, the
   * worker runs and exhausts the queue, another thread enqueues a task and fails to schedule the
   * worker, and then the first thread's call to delegate.execute() returns. Without this counter,
   * it would observe the QUEUING state and set it to QUEUED, and the worker would never be
   * scheduled again for future submissions.
   */
  @GuardedBy("queue")

   * This counter prevents an ABA issue where a thread may successfully schedule the worker, the
   * worker runs and exhausts the queue, another thread enqueues a task and fails to schedule the
   * worker, and then the first thread's call to delegate.execute() returns. Without this counter,
   * it would observe the QUEUING state and set it to QUEUED, and the worker would never be
   * scheduled again for future submissions.
   */
  @GuardedBy("queue")

    Future<?> scheduled = executorService.schedule(task, delay, timeUnit);
    /*
     * Even when the user interrupts the task, we pass `false` to `cancel` so that we don't
     * interrupt a second time after the interruption performed by TrustedListenableFutureTask.
     */
    task.addListener(() -> scheduled.cancel(false), directExecutor());
    return task;
  }

  /**

   * addListener/SES.schedule. The later racy write in cancel() is not guaranteed to be observed,
   * however that is fine since the correctness is based on the atomic state in our base class. The
   * initial write to timer is never definitely visible to Fire.run since it is assigned after
   * SES.schedule is called. Therefore Fire.run has to check for null. However, it should be visible

 *     implements {@code SuccessorsFunction}, which has a similar API as {@link #children} or can be
 *     the same lambda function as passed into {@link #using(Function)}.
 *     <p>This class is scheduled to be removed in October 2019.
 */
// TODO(b/68134636): Remove by 2019-10
@Deprecated
@Beta
@GwtCompatible
@ElementTypesAreNonnullByDefault
public abstract class TreeTraverser<T> {

  /**