diff --git a/stdlib/argparse.pyi b/stdlib/argparse.pyi
index 3dd6e5617..9dceaabd4 100644
--- a/stdlib/argparse.pyi
+++ b/stdlib/argparse.pyi
@@ -263,7 +263,7 @@ class HelpFormatter:
     def end_section(self) -> None: ...
     def add_text(self, text: Optional[Text]) -> None: ...
     def add_usage(
-        self, usage: Text, actions: Iterable[Action], groups: Iterable[_ArgumentGroup], prefix: Optional[Text] = ...
+        self, usage: Optional[Text], actions: Iterable[Action], groups: Iterable[_ArgumentGroup], prefix: Optional[Text] = ...
     ) -> None: ...
     def add_argument(self, action: Action) -> None: ...
     def add_arguments(self, actions: Iterable[Action]) -> None: ...