code: func FromQuery(req *prompb.Query) (int64, int64, []*labels.Matcher, *storage.SelectParams, error) {
  	matchers, err := fromLabelMatchers(req.Matchers)
  	if err != nil {
  		return 0, 0, nil, nil, err
  	}
  	var selectParams *storage.SelectParams
  	if req.Hints != nil {
  		selectParams = &storage.SelectParams{
  			Start: req.Hints.StartMs,
  			End:   req.Hints.EndMs,
  			Step:  req.Hints.StepMs,
  			Func:  req.Hints.Func,
  		}
  	}
  
  	return req.StartTimestampMs, req.EndTimestampMs, matchers, selectParams, nil
  }
docs: // FromQuery unpacks a Query proto.