diff --git a/docs_src/custom_api_router/tutorial001.py b/docs_src/custom_api_router/tutorial001.py
index d889c7a52..ea8cc9e05 100644
--- a/docs_src/custom_api_router/tutorial001.py
+++ b/docs_src/custom_api_router/tutorial001.py
@@ -91,7 +91,7 @@ class AppRouter(APIRouter):
     def add_route(
         self,
         path: str,
-        endpoint: Callable[[Request], Awaitable[Response] | Response],
+        endpoint: Callable[[Request], Union[Awaitable[Response], Response]],
         methods: list[str] | None = None,
         name: str | None = None,
         include_in_schema: bool = True,