code: func (dc *DisruptionController) getPodReplicaSet(pod *v1.Pod) (*controllerAndScale, error) {
  	controllerRef := metav1.GetControllerOf(pod)
  	if controllerRef == nil {
  		return nil, nil
  	}
  	if controllerRef.Kind != controllerKindRS.Kind {
  		return nil, nil
  	}
  	rs, err := dc.rsLister.ReplicaSets(pod.Namespace).Get(controllerRef.Name)
  	if err != nil {
  		// The only possible error is NotFound, which is ok here.
  		return nil, nil
  	}
  	if rs.UID != controllerRef.UID {
  		return nil, nil
  	}
  	controllerRef = metav1.GetControllerOf(rs)
  	if controllerRef != nil && controllerRef.Kind == controllerKindDep.Kind {
  		// Skip RS if it's controlled by a Deployment.
  		return nil, nil
  	}
  	return &controllerAndScale{rs.UID, *(rs.Spec.Replicas)}, nil
  }
docs: // getPodReplicaSet finds a replicaset which has no matching deployments.