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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 dir_tails_target(self, rr_id) -> str: """ Return target directory for revocation registry and tails file production. :param rr_id: revocation registry identifier :return: tails target directory """


        return join(self.dir_tails_top(rr_id), rev_reg_id2cred_def_id(rr_id))