diff --git a/biscuit/apps/chronos/util.py b/biscuit/apps/chronos/util.py
index fe78d98d774c6467de2ccf70846f3a9e052f5c50..85cd40f3954a2eff1ca63f0d91d675cdaf61d608 100644
--- a/biscuit/apps/chronos/util.py
+++ b/biscuit/apps/chronos/util.py
@@ -32,5 +32,5 @@ def current_lesson_periods(when: Optional[datetime] = None) -> models.query.Quer
                                        period__time_end__gte=now.time())
 
 
-def week_weekday_from_date(when: date) -> Sequence[int, int]:
+def week_weekday_from_date(when: date) -> Sequence[int]:
     return (int(when.strftime('%V')), int(when.strftime('%u')))