public PlaylistItemDto Create(PlaylistItemDto playlistItemDto)
        {
            PlaylistItemDto savedPlaylistItemDto;

            using(ITransaction transaction = Session.BeginTransaction())
            {
                Playlist playlist = PlaylistManager.Get(playlistItemDto.PlaylistId);

                SongDto songDto = playlistItemDto.Song;

                PlaylistItem playlistItem = new PlaylistItem(playlistItemDto.Id, playlistItemDto.Title,  playlistItemDto.Cid, songDto.Id, songDto.Type, songDto.Title, songDto.Duration, songDto.Author);
                playlistItemDto.SetPatchableProperties(playlistItem);

                playlist.AddItem(playlistItem);

                PlaylistItemManager.Save(playlistItem);

                savedPlaylistItemDto = PlaylistItemDto.Create(playlistItem);

                transaction.Commit();
            }

            return savedPlaylistItemDto;
        }
        public void Patch(Guid id, PlaylistItemDto playlistItemDto)
        {
            using (ITransaction transaction = Session.BeginTransaction())
            {
                PlaylistItem playlistItem = PlaylistItemManager.Get(id);
                playlistItemDto.SetPatchableProperties(playlistItem);
                PlaylistItemManager.Update(playlistItem);

                transaction.Commit();
            }
        }