code: func (l *LiteBackend) PutRange(ctx context.Context, items []backend.Item) error {
  	for i := range items {
  		if items[i].Key == nil {
  			return trace.BadParameter("missing parameter key in item %v", i)
  		}
  	}
  	err := l.inTransaction(ctx, func(tx *sql.Tx) error {
  		return l.putRangeInTransaction(ctx, tx, items, false)
  	})
  	if err != nil {
  		return trace.Wrap(err)
  	}
  	return nil
  }
docs: // PutRange puts range of items into backend (creates if items doe not
  // exists, updates it otherwise)