internal static bool Insert(Person newPerson)
        {
            if (PersonList.Any(x => x.Fullname == newPerson.Fullname))
            {
                return(false);
            }
            else
            {
                DatabaseService dbService = new DatabaseService();

                PersonList.Add(newPerson);
                dbService.Insert(newPerson);

                return(true);
            }
        }