code: func (s *VolumesService) LocalVolumesSize(ctx context.Context) ([]*types.Volume, error) {
  	ls, _, err := s.vs.Find(ctx, And(ByDriver(volume.DefaultDriverName), CustomFilter(func(v volume.Volume) bool {
  		dv, ok := v.(volume.DetailedVolume)
  		return ok && len(dv.Options()) == 0
  	})))
  	if err != nil {
  		return nil, err
  	}
  	return s.volumesToAPI(ctx, ls, calcSize(true)), nil
  }
docs: // LocalVolumesSize gets all local volumes and fetches their size on disk
  // Note that this intentionally skips volumes which have mount options. Typically
  // volumes with mount options are not really local even if they are using the
  // local driver.