请帮我写一段在Carla中设置npc车辆，使其循环的（创建触发器）只从A点以速度50朝着B点运动的正确代码，触发器创建函数为sensor.other.obstacle

好的，这是在Carla中设置npc车辆，使其循环的代码：

import carla

def set_npc_vehicles_loop(world, spawn_point_a, spawn_point_b):
    blueprint_library = world.get_blueprint_library()
    vehicle_bp = blueprint_library.filter("vehicle.*")[0]
    spawn_points = [spawn_point_a, spawn_point_b]

    # Create a trigger box at spawn_point_a
    trigger_box = world.debug.draw_box(carla.BoundingBox(spawn_point_a.location, carla.Vector3D(2, 2, 2)), carla.Vector3D(), 0.01, carla.Color(255, 0, 0, 0), 0)

    # Create an npc vehicle at spawn_point_a and set its destination to spawn_point_b
    npc_vehicle = world.spawn_actor(vehicle_bp, spawn_point_a)
    npc_vehicle.set_autopilot(True)
    npc_vehicle.set_velocity(carla.Vector3D(50, 0, 0))
    npc_vehicle.set_transform(carla.Transform(spawn_point_a.location, spawn_point_a.rotation))
    npc_vehicle.set_target_location(spawn_point_b.location)

    def on_obstacle_entered(obstacle_actor, obstacle_distance):
        if obstacle_actor == npc_vehicle:
            npc_vehicle.set_transform(carla.Transform(spawn_point_a.location, spawn_point_a.rotation))
            npc_vehicle.set_velocity(carla.Vector3D(50, 0, 0))
            npc_vehicle.set_target_location(spawn_point_b.location))

    # Create a sensor that detects obstacles and bind it to the trigger box
    sensor_bp = blueprint_library.find("sensor.other.obstacle")
    sensor_location = carla.Location(x=0, y=0, z=0)
    sensor_rotation = carla.Rotation(pitch=0, yaw=0, roll=0)
    sensor_transform = carla.Transform(sensor_location, sensor_rotation)
    sensor = world.spawn_actor(sensor_bp, sensor_transform, attach_to=trigger_box)
    sensor.listen(lambda event: on_obstacle_entered(event.other_actor, event.distance))

    return npc_vehicle, trigger_box

你可以调用这个函数来创建一个npc车辆，并在A点和B点之间循环运动：

spawn_point_a = carla.Transform(location=carla.Location(x=100, y=0, z=0))
spawn_point_b = carla.Transform(location=carla.Location(x=200, y=0, z=0))
npc_vehicle, trigger_box = set_npc_vehicles_loop(world, spawn_point_a, spawn_point_b)

请注意，在这个代码中，我们创建了一个触发器盒子，当npc车辆进入该盒子时，它将被重置回A点，并以相同的速度向B点移动。我们还创建了一个传感器，将其绑定到触发器盒子上，以便检测npc车辆何时进入该盒子。当车辆进入盒子时，它将被重置并重新定向到B点。