@Contract(value = "null -> null", pure = true)
  public static @Nullable String generateExternalJavadoc(final @Nullable PsiElement element) {
    if (element == null) return null;

    List<String> docURLs = getExternalJavaDocUrl(element);
    return generateExternalJavadoc(element, docURLs);
  }
@Contract(value = "null -> null", pure = true)
  public static @Nullable String generateExternalJavadoc(final @Nullable PsiElement element)