public static DataManipulatorHandler CreateSingleton(string athleteId, string accessToken)
        {
            if (singletonInstance == null)
            {
                singletonInstance = new DataManipulatorHandler(athleteId, accessToken);
            }

            return(singletonInstance);
        }
        public static DataManipulatorHandler CreateSingleton()
        {
            if (singletonInstance == null)
            {
                singletonInstance = new DataManipulatorHandler();
            }

            return(singletonInstance);
        }