def test_getAndSetNonPrimitiveProperties():
calc = Calculator()
calc.add(3_200_000)
calc.neg()
calc.curr = Multiply(Number(2), calc.curr)
assert calc.value == -6_400_000
def test_callMethods():
calc = Calculator()
calc.add(10)
assert calc.value == 10
calc.mul(2)
assert calc.value == 20
calc.pow(5)
assert calc.value == 20 ** 5
calc.neg()
assert calc.value == -3_200_000
def test_subclassing():
calc = Calculator()
calc.curr = AddTen(33)
calc.neg()
assert calc.value == -43