Make end_time field in Schedule nullable

program/migrations/0059_alter_schedule_end_time.py

+# Generated by Django 3.2.18 on 2023-04-28 22:33
+
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('program', '0058_auto_20230419_0039'),
+    ]
+
+    operations = [
+        migrations.AlterField(
+            model_name='schedule',
+            name='end_time',
+            field=models.TimeField(help_text='End time of schedule.', null=True),
+        ),
+    ]

program/models.py

@@ -342,7 +342,7 @@ class Schedule(models.Model):
         null=True,
         help_text="A tank ID in case the timeslot's playlist_id is empty.",
     )
-    end_time = models.TimeField(help_text="End time of schedule.")
+    end_time = models.TimeField(null=True, help_text="End time of schedule.")
     first_date = models.DateField(help_text="Start date of schedule.")
     is_repetition = models.BooleanField(
         default=False,