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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 _compute_results(self):
 """ Computes the optimum and its value. """

        self.Y_best = best_value(self.Y)
        self.x_opt = self.X[np.argmin(self.Y),:]
        self.fx_opt = np.min(self.Y)