reflex_core.event: provide BaseState as a namespace property

Avoid other weird circular import issues that occur when the `sys.modules`
record for the module is not actually the module namespace.

Author: masenf

packages/reflex-core/src/reflex_core/event.py

@@ -2812,13 +2812,22 @@ def wrapper(
     run_script = staticmethod(run_script)
     __file__ = __file__
 
+    @property
+    def BaseState(self) -> "type[BaseState]":  # noqa: N802
+        """Get the BaseState class.
+
+        A reference to BaseState is needed for doc generation when resolving
+        type hints, so add it to the namespace late to avoid circular import
+        issues.
+
+        Returns:
+            The BaseState class.
+        """
+        from reflex.state import BaseState
+
+        return BaseState
+
 
 event = EventNamespace
 event.event = event  # pyright: ignore[reportAttributeAccessIssue]
 sys.modules[__name__] = event  # pyright: ignore[reportArgumentType]
-
-# A reference to BaseState is needed for doc generation when resolving type
-# hints, so add it to the namespace late to avoid circular import issues.
-from reflex.state import BaseState  # noqa: E402
-
-event.BaseState = BaseState  # pyright: ignore[reportAttributeAccessIssue]