code: func NewNodeClient(stageUnstageSet bool) *NodeClient {
  	return &NodeClient{
  		nodePublishedVolumes: make(map[string]CSIVolume),
  		nodeStagedVolumes:    make(map[string]CSIVolume),
  		stageUnstageSet:      stageUnstageSet,
  	}
  }
docs: // NewNodeClient returns fake node client