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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 _best_dev_gains(rpg):
 """ Calculate the normalized payoff gains from deviating from the current action to the best response for each player. Parameters rpg : RepeatedGame Two player repeated game. Returns ------- best_dev_gains : tuple(ndarray(float, ndim=2)) The normalized best deviation payoff gain arrays. best_dev_gains[i][ai, a-i] is normalized payoff gain player i can get if originally players are choosing ai and a-i, and player i deviates to the best response action. """

    sg, delta = rpg.sg, rpg.delta

    best_dev_gains = ((1-delta)/delta *
                      (np.max(sg.payoff_arrays[i], 0) - sg.payoff_arrays[i])
                      for i in range(2))

    return tuple(best_dev_gains)