code: public UUID addEntity(UUID appId, String versionId, AddEntityOptionalParameter addEntityOptionalParameter) {
          return addEntityWithServiceResponseAsync(appId, versionId, addEntityOptionalParameter).toBlocking().single().body();
      }
docs: Adds an entity extractor to the application.
  
  @param appId The application ID.
  @param versionId The version ID.
  @param addEntityOptionalParameter the object representing the optional parameters to be set before calling this API
  @throws IllegalArgumentException thrown if parameters fail the validation
  @throws ErrorResponseException thrown if the request is rejected by server
  @throws RuntimeException all other wrapped checked exceptions if the request fails to be sent
  @return the UUID object if successful.