code: func CheckTxID(txid string, nonce, creator []byte) error {
  	computedTxID, err := ComputeTxID(nonce, creator)
  	if err != nil {
  		return errors.WithMessage(err, "error computing target txid")
  	}
  
  	if txid != computedTxID {
  		return errors.Errorf("invalid txid. got [%s], expected [%s]", txid, computedTxID)
  	}
  
  	return nil
  }
docs: // CheckTxID checks that txid is equal to the Hash computed
  // over the concatenation of nonce and creator.