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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 _raise_error_if_container_is_missing_an_utterance(self):
 """ Check if there is a dataset for every utterance in every container, otherwise raise an error. """

        expected_keys = frozenset(self.utt_ids)

        for cnt in self.containers:
            keys = set(cnt.keys())

            if not keys.issuperset(expected_keys):
                raise ValueError('Container is missing data for some utterances!')