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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 stats(self):
 """ Return statistics calculated overall samples of all utterances in the corpus. Returns: DataStats: A DataStats object containing statistics overall samples in the corpus. """


        per_utt_stats = self.stats_per_utterance()
        return stats.DataStats.concatenate(per_utt_stats.values())