added a simple sanity checker.

src/documents/migrations/1004_sanity_check_schedule.py

@@ -0,0 +1,26 @@
+# Generated by Django 3.1.3 on 2020-11-25 14:53
+
+from django.db import migrations
+from django.db.migrations import RunPython
+from django_q.models import Schedule
+from django_q.tasks import schedule
+
+
+def add_schedules(apps, schema_editor):
+    schedule('documents.tasks.sanity_check', name="Perform sanity check", schedule_type=Schedule.WEEKLY)
+
+
+def remove_schedules(apps, schema_editor):
+    Schedule.objects.filter(func='documents.tasks.sanity_check').delete()
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('documents', '1003_mime_types'),
+        ('django_q', '0013_task_attempt_count'),
+    ]
+
+    operations = [
+        RunPython(add_schedules, remove_schedules)
+    ]