diff --git a/models/z_schedule.py b/models/z_schedule.py
index ca3f7beef3e441289122fed1ab5308a610704c73..5dbac6a89f3acf43c438f225b8b1d0ec5d50b14e 100644
--- a/models/z_schedule.py
+++ b/models/z_schedule.py
@@ -1,4 +1,5 @@
 from room_util import ROOM_CLOSE
+from datetime import timedelta
 
 if db(db.Meta).count() > 0:
     seconds_passed = (request.now - db(db.Meta).select().first().schedule).total_seconds()