style: clang-tidy: modernize-use-using
diff --git a/include/pybind11/pybind11.h b/include/pybind11/pybind11.h
index 9f1736f..c6334fb 100644
--- a/include/pybind11/pybind11.h
+++ b/include/pybind11/pybind11.h
@@ -1789,7 +1789,7 @@
           typename KeyType = decltype((*std::declval<Iterator>()).first),
           typename... Extra>
 iterator make_key_iterator(Iterator first, Sentinel last, Extra &&... extra) {
-    typedef detail::iterator_state<Iterator, Sentinel, true, Policy> state;
+    using state = detail::iterator_state<Iterator, Sentinel, true, Policy>;
 
     if (!detail::get_type_info(typeid(state), false)) {
         class_<state>(handle(), "iterator", pybind11::module_local())