my_van.at_dead_end()my_van.at_destination()my_van.at_red_traffic_light()my_van.at_green_traffic_light()my_van.at_traffic_light(c)# where c is 'RED' or 'GREEN'
my_van.is_road_forward()my_van.is_road_left()my_van.is_road_right()my_van.is_road(d)# where d is 'FORWARD', 'LEFT', or 'RIGHT'