diff --git a/vllm/block.py b/vllm/block.py
index 3549ee4e9d77a..e3231ae592f91 100644
--- a/vllm/block.py
+++ b/vllm/block.py
@@ -1,5 +1,5 @@
 """Token blocks."""
-from typing import Optional, List
+from typing import List, Optional
 
 from vllm.utils import Device