@NotNull
  private static Set<Key<?>> getPublicKeys() {
    Set<Key<?>> result = new HashSet<>(DATA_KEYS);
    for (ExternalProjectStructureCustomizer customizer : ExternalProjectStructureCustomizer.EP_NAME.getExtensions()) {
      result.addAll(customizer.getPublicDataKeys());
    }
    return result;
  }
@NotNull
  private static Set<Key<?>> getPublicKeys()