executeCallbacks.stream().forEach(callback -> callback.accept(error));
            } catch (final Exception ignore) {}
        }
        latch.countDown();
    }

    public Promise then(final Consumer<RESPONSE> consumer) {
        return promise.then(consumer);
    }

    public Promise error(final Consumer<Throwable> consumer) {
        return promise.error(consumer);
    }

    public Promise promise() {

	// for multiple endpoints.
	Version(context.Context) (string, error)

	// APIs returns a list of APIs supported by the KMS server.
	//
	// TODO(aead): remove this API call. It's hardly useful.
	APIs(context.Context) ([]madmin.KMSAPI, error)

	// Stat returns the current KMS status.
	Status(context.Context) (map[string]madmin.ItemState, error)

	// CreateKey creates a new key at the KMS with the given key ID.

	ch2 := make(chan Maskable, 1)
	doneCh := make(chan struct{})
	defer close(doneCh)
	if err := ps.Subscribe(MaskAll, ch1, doneCh, nil); err != nil {
		t.Fatalf("unexpected error: %v", err)
	}
	if err := ps.Subscribe(MaskAll, ch2, doneCh, nil); err != nil {
		t.Fatalf("unexpected error: %v", err)
	}
	ps.Lock()
	defer ps.Unlock()

	if len(ps.subs) != 2 || ps.NumSubscribers(MaskAll) != 2 || ps.Subscribers() != 2 {

                          &numerical_grad_raw);
    ASSERT_EQ(errors::OK, s.code()) << s.message();
    numerical_grad.reset(numerical_grad_raw);
  }

  TF_Tensor* numerical_tensor;
  s = GetValue(numerical_grad.get(), &numerical_tensor);
  ASSERT_EQ(errors::OK, s.code()) << s.message();
  auto num_elem_numerical = TF_TensorElementCount(numerical_tensor);

type NetlinkDependencies interface {
	AddInpodMarkIPRule(cfg *Config) error
	DelInpodMarkIPRule(cfg *Config) error
	AddLoopbackRoutes(cfg *Config) error
	DelLoopbackRoutes(cfg *Config) error
}

func RealNlDeps() NetlinkDependencies {
	return &realDeps{}
}

type realDeps struct{}

func (r *realDeps) AddInpodMarkIPRule(cfg *Config) error {
	return AddInpodMarkIPRule(cfg)
}

  @Override
  public void run() {
    T result = null;
    Throwable error = null;
    if (isDone()) {
      return;
    }
    try {
      result = runInterruptibly();
    } catch (Throwable t) {
      error = t;
    }
    if (error == null) {
      // The cast is safe because of the `run` and `error` checks.
      afterRanInterruptiblySuccess(uncheckedCastNullableTToT(result));
    } else {

)

func (f fatalMsg) pretty(msg string, args ...interface{}) {
	// Build the passed error message
	errMsg := fmt.Sprintf(msg, args...)

	tagPrinted := false

	// Print the error message: the following code takes care
	// of splitting error text and always pretty printing the
	// red banner along with the error message. Since the error
	// message itself contains some colored text, we needed

Renamed FeatureGate RequestManagement...

      raising an error and quitting.

  Returns:
    [String] The value of var_name after querying for input.

  Raises:
    UserInputError: if a query has been attempted n_ask_attempts times without
      success, assume that the user has made a scripting error, and will
      continue to provide invalid input. Raise the error to avoid infinitely
      looping.
  """

```Python hl_lines="1  4"
{!../../docs_src/python_types/tutorial009.py!}
```

Using `Optional[str]` instead of just `str` will let the editor help you detect errors where you could be assuming that a value is always a `str`, when it could actually be `None` too.

`Optional[Something]` is actually a shortcut for `Union[Something, None]`, they are equivalent.