docs: def htmlcolor_to_rgb(str_color):
      """function to convert HTML-styly color string to RGB values
  
      Args:
          s: Color in HTML format
  
      Returns:
          list of three RGB color components
      """
      if not (str_color.startswith('#') and len(str_color) == 7):
          raise ValueError("Bad html color format. Expected: '#RRGGBB' ")
      result = [1.0 * int(n, 16) / 255 for n in (str_color[1:3], str_color[3:5], str_color[5:])]
      return result