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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 color_normalize(src, mean, std=None):
 """Normalize src with mean and std. Parameters src : NDArray Input image mean : NDArray RGB mean to be subtracted std : NDArray RGB standard deviation to be divided Returns ------- NDArray An `NDArray` containing the normalized image. """

    if mean is not None:
        src -= mean
    if std is not None:
        src /= std
    return src