def colorize canvas, color
      canvas.itemconfigure tag, :fill => color
    rescue => ex
      if ex.message =~ /unknown option "-fill"/
        extend CarefulColorize
        colorize canvas, color
      else
        raise
      end
    end
def colorize canvas, color
      canvas.itemconfigure tag, :fill => color
    rescue => ex
      if ex.message =~ /unknown option "-fill"/
        extend CarefulColorize
        colorize canvas, color
      else
        raise
      end
    end
note: call after update, or else color is lost