public void TwoBudgetItemsAreDifferentIfCodesAreDifferent()
{
BudgetItem subject1 = CreateSubject1();
BudgetItem subject2 = CreateSubject2();
Assert.AreNotEqual(subject1, subject2);
Assert.IsTrue(subject1 != subject2);
Assert.AreNotEqual(subject1.GetHashCode(), subject2.GetHashCode());
}