diff --git a/backend/package/yuxi/gateway/__init__.py b/backend/package/yuxi/gateway/__init__.py
index d74c03e4..c9f7378a 100644
--- a/backend/package/yuxi/gateway/__init__.py
+++ b/backend/package/yuxi/gateway/__init__.py
@@ -1,4 +1,5 @@
 from yuxi.gateway.protocol import (
+    PROTOCOL_VERSION,
     ChannelLogoutRequest,
     ChannelStartRequest,
     ChannelStatusRequest,
@@ -11,7 +12,6 @@ from yuxi.gateway.protocol import (
     HelloOk,
     NonEmptyString,
     PositiveInt,
-    PROTOCOL_VERSION,
     RequestFrame,
     ResponseFrame,
     handle_handshake,