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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 _distance_last_evaluations(self):
 """ Computes the distance between the last two evaluations. """

        if self.X.shape[0] < 2:
            # less than 2 evaluations
            return np.inf
        return np.sqrt(np.sum((self.X[-1, :] - self.X[-2, :]) ** 2))