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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 ensure(self, subsystem, name):
 """ Creates a cgroup if it doesn't exist under the specified subsystem and the given name :param subsystem: the cgroup subsystem (currently support 'memory', and 'cpuset') :param name: name of the cgroup to delete """

        args = {
            'subsystem': subsystem,
            'name': name,
        }

        self._cgroup_chk.check(args)
        return self._client.json('cgroup.ensure', args)