code: func (*Service) ListOSes(c context.Context, req *crimson.ListOSesRequest) (*crimson.ListOSesResponse, error) {
  	oses, err := listOSes(c, stringset.NewFromSlice(req.Names...))
  	if err != nil {
  		return nil, err
  	}
  	return &crimson.ListOSesResponse{
  		Oses: oses,
  	}, nil
  }
docs: // ListOSes handles a request to retrieve operating systems.