code: func (ps *PageSetup) PageSetupToFile(name string) error {
  	cstr := C.CString(name)
  	defer C.free(unsafe.Pointer(cstr))
  	var err *C.GError = nil
  	res := C.gtk_page_setup_to_file(ps.native(), cstr, &err)
  	if !gobool(res) {
  		defer C.g_error_free(err)
  		return errors.New(C.GoString((*C.char)(err.message)))
  	}
  	return nil
  }
docs: // PageSetupLoadKeyFile() is a wrapper around gtk_page_setup_load_key_file().
  // PageSetupToFile() is a wrapper around gtk_page_setup_to_file().