diff --git a/stdlib/3/inspect.pyi b/stdlib/3/inspect.pyi
index 665f38d59..10f9b3ff4 100644
--- a/stdlib/3/inspect.pyi
+++ b/stdlib/3/inspect.pyi
@@ -251,7 +251,7 @@ def getclosurevars(func: Callable[..., Any]) -> ClosureVars: ...
 
 def unwrap(func: Callable[..., Any],
            *,
-           stop: Callable[[Any], Any]) -> Any: ...
+           stop: Optional[Callable[[Any], Any]] = ...) -> Any: ...
 
 
 #