code: public ServiceFuture<GroupResult> groupAsync(List<UUID> faceIds, final ServiceCallback<GroupResult> serviceCallback) {
          return ServiceFuture.fromResponse(groupWithServiceResponseAsync(faceIds), serviceCallback);
      }
docs: Divide candidate faces into groups based on face similarity.
  
  @param faceIds Array of candidate faceId created by Face - Detect. The maximum is 1000 faces
  @param serviceCallback the async ServiceCallback to handle successful and failed responses.
  @throws IllegalArgumentException thrown if parameters fail the validation
  @return the {@link ServiceFuture} object