diff --git a/wally/test_run_class.py b/wally/test_run_class.py
index 40ce395..a0c014f 100644
--- a/wally/test_run_class.py
+++ b/wally/test_run_class.py
@@ -1,4 +1,4 @@
-from typing import List, Callable, Any, Dict, Optional, Set, Union
+from typing import List, Callable, Any, Dict, Optional, Set
 from concurrent.futures import ThreadPoolExecutor