public void ReturnsFalseForNotExisting(Guid id)
        {
            var context = InMemoryPoiDbContext.GetPoiDbContextSeeded();
            var repo    = new CityRepository(context);

            Assert.False(repo.CityExists(id));
        }
        public string Save(Student student)
        {
            bool cityExist = cityRepository.CityExists(student.City);

            if (!cityExist)
            {
                throw new ArgumentException("City Does not Exists");
            }

            return(studentReository.Add(student));
        }