code: func (dsc *DaemonSetsController) getDaemonSetsForPod(pod *v1.Pod) []*apps.DaemonSet {
  	sets, err := dsc.dsLister.GetPodDaemonSets(pod)
  	if err != nil {
  		return nil
  	}
  	if len(sets) > 1 {
  		// ControllerRef will ensure we don't do anything crazy, but more than one
  		// item in this list nevertheless constitutes user error.
  		utilruntime.HandleError(fmt.Errorf("user error! more than one daemon is selecting pods with labels: %+v", pod.Labels))
  	}
  	return sets
  }
docs: // getDaemonSetsForPod returns a list of DaemonSets that potentially match the pod.