diff --git a/test/python/test_onedim.py b/test/python/test_onedim.py
index 9fd1d82c988..1beee771e4f 100644
--- a/test/python/test_onedim.py
+++ b/test/python/test_onedim.py
@@ -1356,9 +1356,7 @@ def test_mixture_averaged(self, saveReference=False):
             self.assertFalse(bad, bad)
 
         filename = self.test_work_path / "CounterflowPremixedFlame-h2-mix-RK.csv"
-        # In Python >= 3.8, this can be replaced by the missing_ok argument
-        if filename.is_file():
-            filename.unlink()
+        filename.unlink(missing_ok=True)
 
         sim.write_csv(filename) # check output
         self.assertTrue(filename.is_file())