diff --git a/Lib/importlib/_bootstrap_external.py b/Lib/importlib/_bootstrap_external.py
index 954401cfa85ed3..905d89618993c1 100644
--- a/Lib/importlib/_bootstrap_external.py
+++ b/Lib/importlib/_bootstrap_external.py
@@ -434,6 +434,7 @@ def _write_atomic(path, data, mode=0o666):
 #     Python 3.12a5 3518 (Add RETURN_CONST instruction)
 #     Python 3.12a5 3519 (Modify SEND instruction)
 #     Python 3.12a5 3520 (Remove PREP_RERAISE_STAR, add CALL_INTRINSIC_2)
+#     Python 3.12a5 3521 (Fix refleak)
 
 #     Python 3.13 will start with 3550