code: public static LuisRuntimeAPI authenticate(EndpointAPI endpointAPI, String luisAuthoringKey) {
          return authenticate(String.format("https://%s/luis/v2.0/", endpointAPI.toString()), luisAuthoringKey)
              .withEndpoint(endpointAPI.toString());
      }
docs: Initializes an instance of Language Understanding (LUIS) Runtime API client.
  
  @param endpointAPI the endpoint API
  @param luisAuthoringKey the Language Understanding (LUIS) Authoring API key (see https://www.luis.ai)
  @return the Language Understanding Runtime API client