private static @NotNull PsiClass copyClass(@NotNull PsiClass aClass) {
    Object marker = new Object();
    PsiTreeUtil.mark(aClass, marker);
    PsiElement copy = aClass.getContainingFile().copy();
    PsiElement copyClass = PsiTreeUtil.releaseMark(copy, marker);
    LOG.assertTrue(copyClass != null);
    return (PsiClass)copyClass;
  }
private static @NotNull PsiClass copyClass(@NotNull PsiClass aClass)