code: def rgb2id(color):
      if color.dtype == np.uint8:
          color = color.astype(np.int32)
      return (
          color[:, :, 0]
          + 256 * color[:, :, 1]
          + 256 * 256 * color[:, :, 2]
      )
  
label_desc: Use image node_id 1 for calling a global function with example usage: rgb2id(color) and returns: unknown