diff --git a/test/local_test_cityscapes.py b/test/local_test_cityscapes.py
index 051faaa1b4e4c769a996b94b411b65815eb3a9e7..cff6a993cf34499567398f4107171e66845b18ce 100644
--- a/test/local_test_cityscapes.py
+++ b/test/local_test_cityscapes.py
@@ -50,7 +50,7 @@ if __name__ == "__main__":
         dest="devices",
         help="GPU id of running. if more than one, use spacing to separate.",
         nargs="+",
-        default=0,
+        default=[0],
         type=int)
     args = parser.parse_args()