code: func (s *server) GetSessions(namespace string) ([]Session, error) {
  	prefix := activePrefix(namespace)
  
  	result, err := s.bk.GetRange(context.TODO(), prefix, backend.RangeEnd(prefix), MaxSessionSliceLength)
  	if err != nil {
  		return nil, trace.Wrap(err)
  	}
  	out := make(Sessions, 0, len(result.Items))
  
  	for i := range result.Items {
  		var session Session
  		if err := json.Unmarshal(result.Items[i].Value, &session); err != nil {
  			return nil, trace.Wrap(err)
  		}
  		out = append(out, session)
  	}
  	sort.Stable(out)
  	return out, nil
  }
docs: // GetSessions returns a list of active sessions. Returns an empty slice
  // if no sessions are active