當(dāng)我運(yùn)行程序時(shí)，畫布會(huì)顯示出來，但圖像不會(huì)顯示。canvas = Canvas(frame, width = 128, height = 128, bg= 'white')    image_data = Image.open('NoArt.gif')    ppm_f = ImageTk.PhotoImage(image_data)    canvas.create_image(0, 0, image = ppm_f, anchor = NW)    canvas.pack(side=BOTTOM)有任何想法嗎？？PS。我有PIL ver 1.6，python 2.6和python 2.6隨附的Tkinter版本