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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 clear_all(self):
 """Delete all Mentions from given split the database."""

        logger.info("Clearing ALL Mentions.")
        self.session.query(Mention).delete(synchronize_session="fetch")

        # With no Mentions, there should be no Candidates also
        self.session.query(Candidate).delete(synchronize_session="fetch")
        logger.info("Cleared ALL Mentions (and Candidates).")