public List <User> GetUsersByLastName(string lastName)
        {
            List <User> result  = new List <User>();
            var         fbUsers = fbApi.GetAccounts(lastName, 100000);

            if (fbUsers != null)
            {
                int i = 1;
                foreach (var fbUser in fbUsers)
                {
                    result.Add(new User
                    {
                        FullName = fbUser.FirstName + " " + fbUser.LastName,
                        Id       = i++
                    });
                }
            }
            return(result);
        }