243     def _run(self, cmd, *args, **kwargs):  member in ChromiumOSProvisioner
253         return self._run('rootdev %s' % options).stdout.strip()
257         self._run('stop ui || true')
258         self._run('stop update-engine || true; start update-engine')
271         self._run(cmd)
279         self._run('echo %s > %s' % (version_number, _TARGET_VERSION))
285         return self._run('/postinst %s 2>&1' % part)
314         first_line = self._run(fetch_script).stdout.strip()
345             self._run('touch %s' % PROVISION_FAILED)
371         self._run('curl -s -o /dev/null %s' % gs_cache_url)
375         self._run(command)
405         self._run(command)
424         self._run(command)
491         self._run('crossystem clear_tpm_owner_request=1', ignore_status=True)
500         self._run(autoreboot_cmd % LAB_MACHINE_FILE)
508             self._run('touch %s' % PROVISION_FAILED)
515             self._run('rm -rf ' + installed_autodir)