def vehicle_interface_test(vh: Vehicle):
if not isinstance(vh, Vehicle):
raise ValueError('vh must be derived from Vehicle')
test_count = 0
if isinstance(vh, CarradioMixin):
vh.carradio_on()
vh.carradio_scan()
vh.carradio_volume = 10
print(f'Now the carradio volume is {vh.carradio_volume}')
vh.carradio_off()
test_count += 1
if isinstance(vh, NavigatorMixin):
vh.navigator_on()
vh.navigator_set_start_point('start')
vh.navigator_set_end_point('end')
vh.navigator_get_route()
vh.navigator_off()
test_count += 1
if test_count == 0:
print(
'Interface test: no additional equipment is installed in the vehicle'
)
