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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 update_ostree_summary(self, release):
 """Update the ostree summary file and return a path to it"""

        self.log.info('Updating the ostree summary for %s', release['name'])
        self.mock_chroot(release, release['ostree_summary'])
        return os.path.join(release['output_dir'], 'summary')