public void DeserializeAndFlattenWorks()
        {
            DirectoryInfo testDataDir = CommonTestHelpers.FindTestDataDirectory();

            IJsonSerializer serializer = new SystemTextJsonSerializer();

            foreach (var file in testDataDir.EnumerateFiles("*.json"))
            {
                string json = File.ReadAllText(file.FullName);
                List <KeyValuePair <string, object> > result = serializer.DeserializeAndFlatten(json).ToList();
            }
        }