def test_init(self):
        r = Road(3, 20, None)
        self.assertEqual(3, r.getLanesCount())
        self.assertEqual(20, r.getLength())
        self.assertEqual(r.carCount(), 0)

        # road is empty, so we should be able to add a car
        self.assertTrue(r.addCar())
        self.assertEqual(1, r.carCount())
    def test_init(self):
        r = Road(3, 20, None)
        self.assertEqual(3, r.getLanesCount())
        self.assertEqual(20, r.getLength())
        self.assertEqual(r.carCount(), 0)

        # road is empty, so we should be able to add a car
        self.assertTrue(r.addCar())
        self.assertEqual(1, r.carCount())