diff --git a/stdlib/2and3/contextlib.pyi b/stdlib/2and3/contextlib.pyi
index 404c7f0a3..c747ab547 100644
--- a/stdlib/2and3/contextlib.pyi
+++ b/stdlib/2and3/contextlib.pyi
@@ -64,7 +64,7 @@ if sys.version_info >= (3, 5):
 
 if sys.version_info >= (3,):
     class ContextDecorator:
-        def __call__(self, func: Callable[..., None]) -> Callable[..., ContextManager[None]]: ...
+        def __call__(self, func: _F) -> _F: ...
     _U = TypeVar("_U", bound=ExitStack)
     class ExitStack(ContextManager[ExitStack]):
         def __init__(self) -> None: ...