Add previous_live_lesson getter to SchoolSchedule

apps/school/models.py

@@ -1,3 +1,5 @@
+from datetime import timedelta
+
 from django.db import models
 from django.utils.timezone import now
 
@@ -59,14 +61,22 @@ class SchoolSchedule(models.Model):
 
     def current_live_lesson(self):
         now_time = now()
-        weekday = self.weekday
         live_lesson = LiveLesson.objects.filter(
-            date__week_day=weekday + 1 if weekday % 7 else 1,
+            date__week_day=self.weekday + 1 if self.weekday % 7 else 1,
             date__week=now_time.date().isocalendar()[1],
             deactivated_at__isnull=True,
         ).first()
         return live_lesson
 
+    def previous_live_lesson(self):
+        now_time = now()
+        live_lesson = LiveLesson.objects.filter(
+            date__week_day=self.weekday + 1 if self.weekday % 7 else 1,
+            date__week=(now_time.date() - timedelta(weeks=1)).isocalendar()[1],
+            deactivated_at__isnull=True,
+        ).first()
+        return live_lesson
+
 
 class SchoolScheduleImage(models.Model):
     schoolschedule = models.ForeignKey(