code: public UUID createRegexEntityModel(UUID appId, String versionId, RegexModelCreateObject regexEntityExtractorCreateObj) {
          return createRegexEntityModelWithServiceResponseAsync(appId, versionId, regexEntityExtractorCreateObj).toBlocking().single().body();
      }
docs: Adds a regex entity model to the application version.
  
  @param appId The application ID.
  @param versionId The version ID.
  @param regexEntityExtractorCreateObj A model object containing the name and regex pattern for the new regex entity extractor.
  @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.