code: function getAuthenticator(options) {
  
    if (options.requestAuthenticator) {
      return options.requestAuthenticator;
    }
  
    var apiKey = options.client ? options.client.apiKey : options.apiKey;
  
    if (!apiKey) {
      throw new Error('If you do not specify a \'requestAuthenticator\' field, you must specify an ApiKey.');
    }
  
    var authc = new BasicRequestAuthenticator(apiKey); //default until Sauthc1 is working.
  
    if (options.authenticationScheme) {
      var scheme = options.authenticationScheme.toUpperCase();
  
      if (scheme === 'SAUTHC1') {
        authc = new Sauthc1RequestAuthenticator(apiKey);
      } else if (scheme === 'BASIC') {
        authc = new BasicRequestAuthenticator(apiKey);
      } else {
        throw new Error("Unrecognized authentication scheme: " + options.authenticationScheme);
      }
    }
  
    return authc;
  }
docs: @private
  
  @description
  
  A factory function that inspects any options and returns an appropriate {@link RequestAuthenticator} to use to
  authenticate requests submitted to the API server.
  
  @param {object} options
  @param {Sauthc1RequestAuthenticator|BasicRequestAuthenticator=} options.requestAuthenticator
  @param {string} options.authenticationScheme - name of auth method that will instantiated
  @returns {BasicRequestAuthenticator|Sauthc1RequestAuthenticator}