diff --git a/mamba/nodetransformers.py b/mamba/nodetransformers.py
index 5b46f12..da31e51 100644
--- a/mamba/nodetransformers.py
+++ b/mamba/nodetransformers.py
@@ -204,5 +204,6 @@ class TransformToSpecsPython3NodeTransformer(TransformToSpecsNodeTransformer):
             kwonlyargs=[],
             kw_defaults=[],
             kwarg=None,
-            defaults=[]
+            defaults=[],
+            posonlyargs=[]
         )