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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 _update_u(u, W):
 """ Update the threat points if it not feasible in the new W, by the minimum of new feasible payoffs. Parameters u : ndarray(float, ndim=1) The threat points. W : ndarray(float, ndim=1) The points that construct the feasible payoff convex hull. Returns ------- u : ndarray(float, ndim=1) The updated threat points. """

    for i in range(2):
        W_min = W[:, i].min()
        if u[i] < W_min:
            u[i] = W_min

    return u