code: func NewTxStatusEvent(txID string, txValidationCode pb.TxValidationCode, blockNum uint64, sourceURL string) *fab.TxStatusEvent {
  	return &fab.TxStatusEvent{
  		TxID:             txID,
  		TxValidationCode: txValidationCode,
  		BlockNumber:      blockNum,
  		SourceURL:        sourceURL,
  	}
  }
docs: // NewTxStatusEvent creates a new TxStatusEvent