code: def _trim_css_to_bounds(css, image_shape):
      
      return max(css[0], 0), min(css[1], image_shape[1]), min(css[2], image_shape[0]), max(css[3], 0)
docs: Make sure a tuple in (top, right, bottom, left) order is within the bounds of the image.
  
      :param css:  plain tuple representation of the rect in (top, right, bottom, left) order
      :param image_shape: numpy shape of the image array
      :return: a trimmed plain tuple representation of the rect in (top, right, bottom, left) order