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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 treeplot(self, qlist, credible_interval):
 """Get data for each treeplot for the variable."""

        for y, _, label, values, color in self.iterator():
            ntiles = np.percentile(values.flatten(), qlist)
            ntiles[0], ntiles[-1] = hpd(values.flatten(), credible_interval)
            yield y, label, ntiles, color