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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def get_img_data(f, maxsize = (1200, 850), first = False):
 """Generate image data using PIL """

    img = Image.open(f)
    img.thumbnail(maxsize)
    if first:                     # tkinter is inactive the first time
        bio = io.BytesIO()
        img.save(bio, format = "PNG")
        del img
        return bio.getvalue()
    return ImageTk.PhotoImage(img)