diff --git a/aleksis/apps/chronos/util/date.py b/aleksis/apps/chronos/util/date.py
index f17aa0ba8354b9dce1ed9db5ee158954afc71ea0..feb63bc8de2f7e3c9ea0dc68a6d4b187b5c80d0b 100644
--- a/aleksis/apps/chronos/util/date.py
+++ b/aleksis/apps/chronos/util/date.py
@@ -8,19 +8,22 @@ from django.utils.translation import gettext_lazy as _
 
 
 def week_weekday_from_date(when: date) -> Tuple[CalendarWeek, int]:
+    """Return a tuple of week and weekday from a given date."""
     return (CalendarWeek.from_date(when), when.weekday())
 
 
 def week_weekday_to_date(week: CalendarWeek, weekday: int) -> date:
+    """Return a date object for one day in a calendar week."""
     return week[weekday - 1]
 
 
 def week_period_to_date(week: Union[CalendarWeek, int], period) -> date:
+    """Return the date of a lesson period in a given week."""
     return period.get_date(week)
 
 
 def get_weeks_for_year(year: int) -> List[CalendarWeek]:
-    """ Generates all weeks for one year """
+    """Generate all weeks for one year."""
     weeks = []
 
     # Go for all weeks in year and create week list