private async Task <MangaInfo[]> CreateDictionary() { var mangaData = await _memCache.GetAsync(); var metaData = await _metaDataService.GetMetaData(); var metaDataDict = metaData.Where(m => !string.IsNullOrEmpty(m.name)) .GroupBy(m => m.name) .ToDictionary(m => m.Key, x => x.First().metaData); var dict = mangaData // .GroupBy(t => t.name, t => (t.provider, t.url)) .Select(g => new MangaInfo { Name = g.Key, Instances = g.ToList(), MetaData = metaDataDict.ContainsKey(g.Key) ? metaDataDict[g.Key] : default })