old_contents: import os
  import click
  import cv2
  from AppKit import NSScreen
  
  
  def check_image(filename, height):
      image = cv2.imread(filename)
      image_name = os.path.basename(filename)
      is_positive = _check(image, image_name, height)
      return image_name, is_positive
  
  
  def _check(image, image_name, target_height):
      cv2.namedWindow(image_name, cv2.WINDOW_NORMAL)
      while True:
          height, width = image.shape[:2]
          scaling_f = height / target_height
          small = cv2.resize(image, None, fx=1/scaling_f, fy=1/scaling_f)
          # display the image and wait for a keypress
          cv2.imshow(image_name, small)
          key = cv2.waitKey(1)
  
          # if the 'y' key is pressed return True
          if key == ord("y"):
              cv2.destroyWindow(image_name)
              print('True')
              return True
  
          # if the 'n' key is pressed return False
          elif key == ord("n"):
              print('False')
              cv2.destroyWindow(image_name)
              return False
  
  
  @click.command()
  @click.argument('files',
                nargs=-1, type=click.Path(exists=True))
  @click.option('--output_path',
                help='Write result here',
                default=None,
                type=click.Path(exists=False))
  def check_files(files, output_path):
      height = NSScreen.mainScreen().frame().size.height
      with open(output_path, 'w') as out:
          for file in files:
              image_name, is_positive = check_image(file, height)
              template = "%s\t%s\n"
              out.write(template % (image_name, is_positive))
  
  
  if __name__ == "__main__":
      check_files()
new_contents: """Goes through a list of images. The user can press 'n' or 'y',
  which will cause True or False to be written in the output file as a column next to the filename.
  Prerequisite is a function opencv library (on OSX can be installed by brew install opencv), pyobjc (pip install pyobjc)
  and opencv-python
  """
  
  import os
  import click
  import cv2
  from AppKit import NSScreen
  
  
  def check_image(filename, height):
      image = cv2.imread(filename)
      image_name = os.path.basename(filename)
      is_positive = _check(image, image_name, height)
      return image_name, is_positive
  
  
  def _check(image, image_name, target_height):
      cv2.namedWindow(image_name, cv2.WINDOW_NORMAL)
      while True:
          height, width = image.shape[:2]
          scaling_f = height / target_height
          small = cv2.resize(image, None, fx=1 / scaling_f, fy=1 / scaling_f)
          # display the image and wait for a keypress
          cv2.imshow(image_name, small)
          key = cv2.waitKey(1)
  
          # if the 'y' key is pressed return True
          if key == ord("y"):
              cv2.destroyWindow(image_name)
              print('True')
              return True
  
          # if the 'n' key is pressed return False
          elif key == ord("n"):
              print('False')
              cv2.destroyWindow(image_name)
              return False
  
          # if the 'm' key is pressed return Maybe
          elif key == ord("m"):
              print('Maybe')
              cv2.destroyWindow(image_name)
              return 'Maybe'
  
  
  @click.command()
  @click.argument('files',
                  nargs=-1, type=click.Path(exists=True))
  @click.option('--output_path',
                help='Write result here',
                default=None,
                type=click.Path(exists=False))
  def check_files(files, output_path):
      height = NSScreen.mainScreen().frame().size.height
      with open(output_path, 'w') as out:
          for file in files:
              image_name, is_positive = check_image(file, height)
              template = "%s\t%s\n"
              out.write(template % (image_name, is_positive))
  
  
  if __name__ == "__main__":
      check_files()
  
subject: Add 'maybe' key to check_calls.py