public List <string> GetCacheKeysExample1()
        {
            ICacheManager cacheManager = new MemoryCacheManager();
            string        inputString  = Console.ReadLine();
            const string  cacheKey     = "MyKey";
            const double  saveHours    = 1;

            cacheManager.SetByAbsolute(cacheKey, inputString, saveHours);
            List <string> allKeys = cacheManager.GetCacheKeys();

            return(allKeys);
        }