public void TestAddNewPart()
{
// Arrange
PartRepository partRepository = new PartRepository();
partRepository.AddNewPart(new Part(1, "111", "Audi", "A6", "Brake disc front", new PartCategory(1, "1", "Brakes"), new PartLocation(1, "A1", "Green")));
int expected = 9;
// Act
int actual = partRepository.Retrieve().Count;
// Assert
Assert.AreEqual(expected, actual);
}