code: def signal_handler(signum, _):
      print("\nReceived signal {}. Trigger stopping...".format(signum))
      VehicleControl.signal_received = True
  
imports: from __future__ import print_function
  import glob
  import os
  import sys
  import signal
  import carla
  from carla import ColorConverter
  import argparse
  import logging
  import math
  import random
  import weakref
  from rss_sensor import RssSensor
  from rss_visualization import RssUnstructuredSceneVisualizer, RssBoundingBoxVisualizer, RssStateVisualizer
label_desc: Use image node_id 3 for calling the VehicleControl obj's underlying member method code with example usage: obj.signal_handler(signum, _) without return types