diff --git a/rbac/check_perm.py b/rbac/check_perm.py
index d18ea5c..4da90c3 100644
--- a/rbac/check_perm.py
+++ b/rbac/check_perm.py
@@ -1,5 +1,6 @@
 import time
 
+from traceback import format_exc
 from aiohttp import BasicAuth
 from sqlor.dbpools import DBPools
 from appPublic.registerfunction import RegisterFunction