code: @BetaApi(
        "The surface for long-running operations is not stable yet and may change in the future.")
    public final OperationFuture<AnnotatedDataset, LabelOperationMetadata> labelAudioAsync(
        LabelAudioRequest request) {
      return labelAudioOperationCallable().futureCall(request);
    }
docs: Starts a labeling task for audio. The type of audio labeling task is configured by feature in
  the request.
  
  <p>Sample code:
  
  <pre><code>
  try (DataLabelingServiceClient dataLabelingServiceClient = DataLabelingServiceClient.create()) {
  String formattedParent = DataLabelingServiceClient.formatDatasetName("[PROJECT]", "[DATASET]");
  HumanAnnotationConfig basicConfig = HumanAnnotationConfig.newBuilder().build();
  LabelAudioRequest.Feature feature = LabelAudioRequest.Feature.FEATURE_UNSPECIFIED;
  LabelAudioRequest request = LabelAudioRequest.newBuilder()
  .setParent(formattedParent)
  .setBasicConfig(basicConfig)
  .setFeature(feature)
  .build();
  AnnotatedDataset response = dataLabelingServiceClient.labelAudioAsync(request).get();
  }
  </code></pre>
  
  @param request The request object containing all of the parameters for the API call.
  @throws com.google.api.gax.rpc.ApiException if the remote call fails