@Nullable
  public PsiElement getPsiElement(@NotNull FoldRegion region) {
    final SmartPsiElementPointer<?> pointer = myFoldRegionToSmartPointerMap.get(region);
    if (pointer == null) {
      return null;
    }
    PsiElement element = pointer.getElement();
    return element != null && element.isValid() ? element : null;
  }
@Nullable
  public PsiElement getPsiElement(@NotNull FoldRegion region)