diff --git a/test/flags_test.py b/test/flags_test.py
index c4954c4..d25289b 100644
--- a/test/flags_test.py
+++ b/test/flags_test.py
@@ -7,4 +7,4 @@
 class FlagsTest(unittest.TestCase):
 
     def test_flags(self):
-        self.assertEqual('--test_flag', sys.argv[1])
+        self.assertIn("--test_flag", sys.argv)