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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 ostree_init(self, release):
 """Initialize the OSTree for a release"""

        out = release['output_dir'].rstrip('/')
        base = os.path.dirname(out)
        if not os.path.isdir(base):
            self.log.info('Creating %s', base)
            os.makedirs(base, mode=0755)
        if not os.path.isdir(out):
            self.mock_chroot(release, release['ostree_init'])