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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 rev_regs(self) -> list: """ Return list of revocation registry identifiers for which HolderProver has tails files. :return: list of revocation registry identifiers for which HolderProver has tails files """


        LOGGER.debug('HolderProver.rev_regs >>>')

        rv = [basename(f) for f in Tails.links(self._dir_tails)]
        LOGGER.debug('HolderProver.rev_regs <<< %s', rv)
        return rv