diff --git a/python/MooreTests/list_event_numbers.py b/python/MooreTests/list_event_numbers.py
index 6cd51894e168be2be1f59f2c3a09fcb3cd03bbcd..03b98d70569278239c7e8c5670f4a524a4f87369 100755
--- a/python/MooreTests/list_event_numbers.py
+++ b/python/MooreTests/list_event_numbers.py
@@ -80,7 +80,7 @@ def main():
         type=str,
         required=True,
         choices=['hlt2', 'spruce'],
-        "Stage of the trigger.")
+        help="Stage of the trigger.")
     parser.add_argument(
         '-sc',
         '--stream-config',