diff --git a/src/dependency_injector/containers.pyi b/src/dependency_injector/containers.pyi
index 78057e7d..472996c9 100644
--- a/src/dependency_injector/containers.pyi
+++ b/src/dependency_injector/containers.pyi
@@ -73,7 +73,7 @@ class Container:
         modules: Optional[Iterable[Any]] = None,
         packages: Optional[Iterable[Any]] = None,
         from_package: Optional[str] = None,
-        keep_cache: bool | None = None,
+        keep_cache: Optional[bool] = None,
         warn_unresolved: bool = False,
     ) -> None: ...
     def unwire(self) -> None: ...