_unwrap_restricted_proxy helper

Author: dandavison

temporalio/worker/workflow_sandbox/_restrictions.py

@@ -950,13 +950,20 @@ def _is_restrictable(v: Any) -> bool:
     )
 
 
+def _unwrap_restricted_proxy(v: Any) -> Any:
+    # TODO: __wrapped__ should do this but it's broken.
+    if isinstance(v, _RestrictedProxy):
+        return object.__getattribute__(v, "__temporal_state").obj
+    return v
+
+
 class _RestrictedProxy:
     @classmethod
     def __get_pydantic_core_schema__(
         cls, source_type: Any, handler: GetCoreSchemaHandler
     ) -> CoreSchema:
         return core_schema.no_info_after_validator_function(
-            cls, handler(object.__getattribute__(source_type, "__temporal_state").obj)
+            cls, handler(_unwrap_restricted_proxy(source_type))
         )
 
     def __init__(self, *args, **kwargs) -> None: