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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(prediction, fix):
 """ Compute the normalized scanpath salience input: fix : list, l[0] contains y, l[1] contains x """


    prediction = prediction - np.mean(prediction)
    prediction = prediction / np.std(prediction)
    return np.mean(prediction[fix[0], fix[1]])