code: func (n *Node) stopWS() {
  	if n.wsListener != nil {
  		n.wsListener.Close()
  		n.wsListener = nil
  
  		n.log.Info("WebSocket endpoint closed", "url", fmt.Sprintf("ws://%s", n.wsEndpoint))
  	}
  	if n.wsHandler != nil {
  		n.wsHandler.Stop()
  		n.wsHandler = nil
  	}
  }
docs: // stopWS terminates the websocket RPC endpoint.