def rebase_dates(self, topics):
        print 'Rebasing dates...',
        delta = datetime.utcnow() - self.highest_date
        for topic in topics:
            topic.last_change += delta
            topic.date += delta
            for post in topic.posts:
                post.updated += delta
                post.created += delta
                for comment in post.comments:
                    comment.date += delta
            topic._update_hotness()
        print 'done'
Return a list of folder names.
dataset/ETHPy150Open mitsuhiko/solace/solace/scripts.py/MakeTestDataCommand.rebase_dates--crossover with--dataset/ETHPy150Open babble/babble/include/jython/Lib/mailbox.py/Maildir.list_folders