public static @Nullable List<? extends PsiElement> getAllPsiElements(@NotNull LookupElement item) {
    List<PsiMethod> allMethods = getAllMethods(item);
    if (allMethods != null) return allMethods;
    if (item.getObject() instanceof PsiElement) return Collections.singletonList((PsiElement)item.getObject());
    return null;
  }
public static @Nullable List<? extends PsiElement> getAllPsiElements(@NotNull LookupElement item)