code: func (itr *pvtdataResultsItr) Next() (commonledger.QueryResult, error) {
  	queryResult, err := itr.dbItr.Next()
  	if err != nil {
  		return nil, err
  	}
  	if queryResult == nil {
  		return nil, nil
  	}
  	versionedQueryRecord := queryResult.(*statedb.VersionedKV)
  	return &queryresult.KV{
  		Namespace: itr.ns,
  		Key:       versionedQueryRecord.Key,
  		Value:     versionedQueryRecord.Value,
  	}, nil
  }
docs: // Next implements method in interface ledger.ResultsIterator