public IEnumerable <PresidentModel> GetAllPresidents()
        {
            List <President>      presidents      = new List <President>();
            List <PresidentModel> presidentsModel = new List <PresidentModel>();

            presidents = _contentItemRepository.GetAllPresidents().ToList();

            foreach (var item in presidents)
            {
                PresidentModel president = new PresidentModel
                {
                    id         = item.id,
                    Name       = item.name,
                    Birthday   = item.birthday,
                    Birthplace = item.birthplace,
                    Deathday   = item.deathday,
                    Deathplace = item.deathplace
                };

                presidentsModel.Add(president);
            }

            return(presidentsModel);
        }