code: func (s *SupportImpl) GetTransactionByID(chid, txID string) (*pb.ProcessedTransaction, error) {
  	lgr := s.Peer.GetLedger(chid)
  	if lgr == nil {
  		return nil, errors.Errorf("failed to look up the ledger for Channel %s", chid)
  	}
  	tx, err := lgr.GetTransactionByID(txID)
  	if err != nil {
  		return nil, errors.WithMessage(err, "GetTransactionByID failed")
  	}
  	return tx, nil
  }
docs: // GetTransactionByID retrieves a transaction by id