code: func newRedeemingTxNotification(txHex string, index int, block *btcutil.Block) ([]byte, error) {
  	// Create and marshal the notification.
  	ntfn := btcjson.NewRedeemingTxNtfn(txHex, blockDetails(block, index))
  	return btcjson.MarshalCmd(nil, ntfn)
  }
docs: // newRedeemingTxNotification returns a new marshalled redeemingtx notification
  // with the passed parameters.