code: def _close_server(self):
      os.killpg(os.getpgid(self.server.pid), signal.SIGKILL)
  
imports: import random
  import sys
  from os import path, environ
  from rl_coach.logger import screen
  from rl_coach.filters.action.partial_discrete_action_space_map import PartialDiscreteActionSpaceMap
  from rl_coach.filters.observation.observation_rgb_to_y_filter import ObservationRGBToYFilter
  from rl_coach.filters.observation.observation_to_uint8_filter import ObservationToUInt8Filter
  import os
  import signal
  import logging
  import subprocess
  import numpy
  from rl_coach.environments.environment import Environment, EnvironmentParameters, LevelSelection
  from rl_coach.spaces import BoxActionSpace, ImageObservationSpace, StateSpace, VectorObservationSpace
  from rl_coach.utils import get_open_port, force_list
  from enum import Enum
  from typing import List, Union
  from rl_coach.base_parameters import VisualizationParameters
  from rl_coach.filters.filter import InputFilter, NoOutputFilter
  from rl_coach.filters.observation.observation_rescale_to_size_filter import ObservationRescaleToSizeFilter
  from rl_coach.filters.observation.observation_stacking_filter import ObservationStackingFilter
label_desc: Use image node_id 5 for calling the CarlaEnvironment obj's underlying member method code with example usage: obj._close_server() without return types