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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_random_image(img_dir):
 """Pick a random image file from a directory."""

    images, current_wall = get_image_dir(img_dir)

    if len(images) > 2 and current_wall in images:
        images.remove(current_wall)

    elif not images:
        logging.error("No images found in directory.")
        sys.exit(1)

    random.shuffle(images)
    return os.path.join(img_dir, images[0])