Migration path to new models

aleksis/apps/alsijil/models.py

@@ -122,7 +122,7 @@ class Documentation(CalendarEvent):
         start_datetime = CalendarEvent.value_start_datetime(self)
         end_datetime = CalendarEvent.value_end_datetime(self)
         return (
-            f"{','.join(self.get_groups())} {self.get_subject()}"
+            f"{','.join([str(g) for g in self.get_groups()])} {self.get_subject()}"
             + f" {start_datetime} - {end_datetime}"
         )