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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 centerize(src, dst_shape, margin_color=None):
 """Centerize image for specified image size @param src: image to centerize @param dst_shape: image shape (height, width) or (height, width, channel) """

    if src.shape[:2] == dst_shape[:2]:
        return src
    centerized = np.zeros(dst_shape, dtype=src.dtype)
    if margin_color:
        centerized[:, :] = margin_color
    pad_vertical, pad_horizontal = 0, 0
    h, w = src.shape[:2]
    dst_h, dst_w = dst_shape[:2]
    if h < dst_h:
        pad_vertical = (dst_h - h) // 2
    if w < dst_w:
        pad_horizontal = (dst_w - w) // 2
    centerized[pad_vertical:pad_vertical + h,
               pad_horizontal:pad_horizontal + w] = src
    return centerized