def cluster_complete_lifecycle(base, cluster_id, lifecycle_action_token,
    expected_status='SUCCEEDED', wait_timeout=None):
    """Utility function that completes lifecycle for a cluster."""
    params = {'complete_lifecycle': {'lifecycle_action_token':
        lifecycle_action_token}}
    res = base.client.trigger_action('clusters', cluster_id, params=params)
    action_id = res['location'].split('/actions/')[1]
    res = base.client.wait_for_status('actions', action_id, expected_status,
        wait_timeout)
    return res['body']['status_reason']
