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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 cleanup_containers(self):
 """ stop all container created by conu :return: None """

        for cont in self.list_containers():
            if CONU_ARTIFACT_TAG in cont.name:
                try:
                    logger.debug("removing container %s created by conu", cont)
                    # TODO: move this functionality to container.delete
                    run_cmd(["machinectl", "terminate", cont.name])
                except subprocess.CalledProcessError as e:
                    logger.error("unable to remove container %s: %r", cont, e)