diff --git a/execution.py b/execution.py
index e91e9a41..bc5cfe55 100644
--- a/execution.py
+++ b/execution.py
@@ -751,7 +751,7 @@ class PromptQueue:
             if len(self.history) > MAXIMUM_HISTORY_SIZE:
                 self.history.pop(next(iter(self.history)))
 
-            status_dict: dict|None = None
+            status_dict: Optional[dict] = None
             if status is not None:
                 status_dict = copy.deepcopy(status._asdict())