code: public Observable<ServiceResponse<Void>> createWithServiceResponseAsync(String faceListId, CreateFaceListsOptionalParameter createOptionalParameter) {
          if (this.client.azureRegion() == null) {
              throw new IllegalArgumentException("Parameter this.client.azureRegion() is required and cannot be null.");
          }
          if (faceListId == null) {
              throw new IllegalArgumentException("Parameter faceListId is required and cannot be null.");
          }
          final String name = createOptionalParameter != null ? createOptionalParameter.name() : null;
          final String userData = createOptionalParameter != null ? createOptionalParameter.userData() : null;
  
          return createWithServiceResponseAsync(faceListId, name, userData);
      }
docs: Create an empty face list. Up to 64 face lists are allowed to exist in one subscription.
  
  @param faceListId Id referencing a particular face list.
  @param createOptionalParameter the object representing the optional parameters to be set before calling this API
  @throws IllegalArgumentException thrown if parameters fail the validation
  @return the {@link ServiceResponse} object if successful.