diff --git a/third_party/2and3/flask/blueprints.pyi b/third_party/2and3/flask/blueprints.pyi
index 772acdfba..d43f8e4ff 100644
--- a/third_party/2and3/flask/blueprints.pyi
+++ b/third_party/2and3/flask/blueprints.pyi
@@ -24,7 +24,7 @@ class Blueprint(_PackageBoundObject):
     json_decoder: Any = ...
     import_name: str = ...
     template_folder: Optional[str] = ...
-    root_path: Optional[str] = ...
+    root_path: str = ...
     name: str = ...
     url_prefix: Optional[str] = ...
     subdomain: Optional[str] = ...