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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 nss_model(prediction, fm):
 """ wraps nss functionality for model evaluation input: prediction: 2D matrix the model salience map fm : fixmat Fixations that define the actuals """

    (r_y, r_x) = calc_resize_factor(prediction, fm.image_size)
    fix = ((np.array(fm.y-1)*r_y).astype(int),
                            (np.array(fm.x-1)*r_x).astype(int))
    return nss(prediction, fix)