public static void ListenForUsers()
        {
            var listener = new TcpListener(new IPEndPoint(IPAddress.Any, 5050));

            listener.Start();

            while (true)
            {
                try
                {
                    var client = listener.AcceptTcpClient();
                    var user   = new User(client);
                    Users.Add(user);
                    var secondClient = listener.AcceptTcpClient();
                    var user2        = new User(secondClient);
                    //var session = new Session(user);
                    var session = new Session(user, user2);
                    session.StartAsync();
                }
                catch (Exception ex)
                {
                    Console.WriteLine(ex.Message);
                }
            }
        }