public void ChangeItemTest()
        {
            var repo = new StudentsRepository(_context);
            var item = new Student
            {
                FirstName     = "Kurt",
                MiddleName    = "Unknown",
                LastName      = "Wallander",
                Address       = "Ystad",
                Birthday      = new DateTime(1961, 05, 23),
                Email         = "*****@*****.**",
                LogbookNumber = 4366,
                Group         = _context.Groups.FirstOrDefault()
            };

            repo.AddItem(item);
            int Id      = _context.Students.FirstOrDefault(x => x.LogbookNumber == item.LogbookNumber).Id;
            var newitem = repo.GetItem(Id);

            newitem.Email = "*****@*****.**";
            repo.ChangeItem(newitem);
            var gotitem = repo.GetItem(Id);

            Assert.AreEqual(newitem.FirstName, gotitem.FirstName);
            Assert.AreEqual(newitem.MiddleName, gotitem.MiddleName);
            Assert.AreEqual(newitem.LastName, gotitem.LastName);
            Assert.AreEqual(newitem.Address, gotitem.Address);
            Assert.AreEqual(newitem.Birthday, gotitem.Birthday);
            Assert.AreEqual(newitem.Email, gotitem.Email);
            Assert.AreEqual(newitem.LogbookNumber, gotitem.LogbookNumber);
            _context.Students.Remove(newitem);
        }