public async Task <IEnumerable <string> > getKnown(string word)    // Funktioniert nicht
        {
            var listOfWords = await reader.ReadDictionary();

            var knownWords = new HashSet <string>();

            foreach (PairOfWords words in listOfWords)
            {
                if (words.w1 == word || AnagramChecker.IsAnagram(word, words.w1))
                {
                    knownWords.Add(words.w2);
                }
                if (words.w2 == word || AnagramChecker.IsAnagram(word, words.w2))
                {
                    knownWords.Add(words.w1);
                }
            }

            return(knownWords);
        }