public IActionResult Save(string name, string countryCode, string area, int population, string capitalName, string regionName)
        {
            Сountry сountry = new Сountry
            {
                Name        = name,
                СountryCode = countryCode,
                Area        = Convert.ToDecimal(area),
                Population  = population,
                Capital     = new City {
                    Name = capitalName
                },
                Region = new Region {
                    Name = regionName
                }
            };

            _service.AddСountry(сountry);

            return(RedirectToAction(nameof(Index)));
        }