public long Set(string utterance, HttpResponseMessage message)
        {
            var cache = new CachedLuisCache(utterance, message);

            Caches.Add(cache);
            var size = cache.Size;

            TotalBytes  += size;
            Bytes       += size;
            TotalCaches += 1;
            return(Bytes);
        }
        public HttpResponseMessage Get(string utterance)
        {
            // We always add used
            TotalUsed++;
            Used++;

            var input = new CachedLuisCache(utterance, null);

            // TODO: make it first
            if (Caches.Remove(input, out CachedLuisCache output))
            {
                Caches.Add(output);
                return(output.GetMessage());
            }
            else
            {
                return(null);
            }
        }