public Task <List <Match> > GetMatchesAsync()
        {
            var query = @"
                matches {
                    id
                    score1
                    score2
                    player1 {
                        id
                        firstName
                        lastName
                        score
                        teamLogoUrl
                    }
                    player2 {
                        id
                        firstName
                        lastName
                        score
                        teamLogoUrl
                    }
                }
            ";

            return(graphHelper.GetObject <List <Match> >(query, "matches"));
        }
        public Task <List <Player> > GetPlayersAsync()
        {
            var query = @"
                players {
                    id
                    firstName
                    lastName
                    score
                    teamLogoUrl
                }
            ";

            return(graphHelper.GetObject <List <Player> >(query, "players"));
        }