diff --git a/testing/acceptance_test.py b/testing/acceptance_test.py
index bf33f03c6..018279909 100644
--- a/testing/acceptance_test.py
+++ b/testing/acceptance_test.py
@@ -372,7 +372,7 @@ class TestGeneralUsage:
             """
             import pytest
 
-            @pytest.mark.parametrize("a", [a,b,c,a_1])
+            @pytest.mark.parametrize("a", ["a","b","c","a","a1"])
             def test_func(a):
                 pass
             """