diff --git a/source/blender/python/intern/bpy_rna.c b/source/blender/python/intern/bpy_rna.c
index cfd455e045c..ad695344038 100644
--- a/source/blender/python/intern/bpy_rna.c
+++ b/source/blender/python/intern/bpy_rna.c
@@ -2671,6 +2671,9 @@ static PyObject * pyrna_func_call(PyObject *self, PyObject *args, PyObject *kw)
 		RNA_parameter_list_begin(&parms, &iter);
 		for(; iter.valid; RNA_parameter_list_next(&iter)) {
 			parm= iter.parm;
+			if(RNA_property_flag(parm) & PROP_RETURN)
+				continue;
+
 			BLI_dynstr_appendf(good_args, first ? "%s" : ", %s", RNA_property_identifier(parm));
 			first= FALSE;
 		}