code: def diff_images(golden_file_path, new_file_path):
      """Calculates the percentage difference between two images"""
      im_1 = Image.open(golden_file_path)
      im_2 = Image.open(new_file_path)
      assert im_1.mode == im_2.mode, "Different kinds of images"
      assert im_1.size == im_2.size, "Different sizes"
      pairs = zip(im_1.getdata(), im_2.getdata())
      diff = sum(
          abs(c1 - c2) for p1, p2 in pairs for c1, c2 in zip(p1, p2)
      )
      n_components = im_1.size[0] * im_2.size[1] * 3
      return (diff / 255.0 * 100) / n_components
  
label_desc: Use image node_id 1 for calling a global function with example usage: diff_images(golden_file_path, new_file_path) and returns: unknown