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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 repvals(self, method):
 """Compute representative statistical values for this Uval. `method` may be either 'pct' or 'gauss'. Returns (best, plus_one_sigma, minus_one_sigma), where `best` is the "best" value in some sense, and the others correspond to values at the ~84 and 16 percentile limits, respectively. Because of the sampled nature of the Uval system, there is no single method to compute these numbers. The "pct" method returns the 50th, 15.866th, and 84.134th percentile values. The "gauss" method computes the mean μ and standard deviation σ of the samples and returns [μ, μ+σ, μ-σ]. """

        if method == 'pct':
            return pk_scoreatpercentile(self.d, [50., 84.134, 15.866])
        if method == 'gauss':
            m, s = self.d.mean(), self.d.std()
            return np.asarray([m, m + s, m - s])
        raise ValueError('unknown representative-value method "%s"' % method)