code: func (pool *TxPool) Stop() {
  	// Unsubscribe all subscriptions registered from txpool
  	pool.scope.Close()
  	// Unsubscribe subscriptions registered from blockchain
  	pool.chainHeadSub.Unsubscribe()
  	close(pool.quit)
  	log.Info("Transaction pool stopped")
  }
docs: // Stop stops the light transaction pool