Add some explanatory comments

aleksis/apps/alsijil/model_extensions.py

@@ -385,6 +385,9 @@ def generate_person_list_with_class_register_statistics(
     """Get with class register statistics annotated list of all members."""
     if persons is None:
         persons = self.members.all()
+
+    # Build reusable Q objects for filtering by school term and by groups
+    # Necessary for the following annotations
     school_term_q = (
         Q(personal_notes__lesson_period__lesson__validity__school_term=self.school_term)
         | Q(personal_notes__extra_lesson__school_term=self.school_term)

aleksis/apps/alsijil/util/alsijil_helpers.py

@@ -89,7 +89,10 @@ def annotate_documentations(
 
 
 def register_objects_sorter(register_object: Union[LessonPeriod, Event, ExtraLesson]) -> int:
-    """Sort key for sorted/sort for sorting a list of class register objects."""
+    """Sort key for sorted/sort for sorting a list of class register objects.
+
+    This will sort the objects by the start period.
+    """
     if hasattr(register_object, "period"):
         return register_object.period.period
     elif isinstance(register_object, Event):