diff --git a/src/llamafactory/api/chat.py b/src/llamafactory/api/chat.py
index 74b56f73..7f5bf8c4 100644
--- a/src/llamafactory/api/chat.py
+++ b/src/llamafactory/api/chat.py
@@ -14,13 +14,14 @@
 
 import base64
 import io
-import re
 import json
 import os
+import re
 import uuid
-import numpy as np
 from typing import TYPE_CHECKING, AsyncGenerator, Dict, List, Optional, Tuple
 
+import numpy as np
+
 from ..data import Role as DataRole
 from ..extras.logging import get_logger
 from ..extras.packages import is_fastapi_available, is_pillow_available, is_requests_available