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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 img_box(img, box):
 """ Selects the sub-image inside the given box :param img: Image to crop from :param box: Box to crop from. Box can be either Box object or array of [x, y, width, height] :return: Cropped sub-image from the main image """

    if isinstance(box, tuple):
        box = Box.from_tup(box)

    if len(img.shape) == 3:
        return img[box.y:box.y + box.height, box.x:box.x + box.width, :]
    else:
        return img[box.y:box.y + box.height, box.x:box.x + box.width]