code: def cv2_grayscale(image, is_bgr=True, depth=1):
      """Convert a RGB or BGR image to grayscale using OpenCV (cv2).
      :param image: input image, a numpy.ndarray.
      :param is_bgr: tells whether the image is in BGR format. If False, RGB format is assumed.
      :param depth: replicates the gray depth channel multiple times. E.g. useful to display grayscale images as rgb.
      """
      assert depth >= 1
  
      if is_bgr:
          grayscale = cv2.cvtColor(image, cv2.COLOR_BGR2GRAY)
      else:
          grayscale = cv2.cvtColor(image, cv2.COLOR_RGB2GRAY)
  
      if depth > 1:
          return np.stack((grayscale,) * depth, axis=-1)
  
      return grayscale
  
imports: import os
  import cv2
  import math
  import random
  import numpy
  import carla
  import pygame
  import threading
  import datetime
  from typing import Union
  from tensorforce.agents import Agent
label_desc: Use image node_id 15 for calling a global function with example usage: cv2_grayscale(image, is_bgr, depth) and returns: grayscale, np