add default roles to existing users

cookbook/migrations/0036_auto_20200427_1800.py

@@ -0,0 +1,22 @@
+# Generated by Django 3.0.5 on 2020-04-27 16:00
+
+from django.db import migrations
+
+
+def apply_migration(apps, schema_editor):
+    Group = apps.get_model('auth', 'Group')
+    User = apps.get_model('auth', 'User')
+    for u in User.objects.all():
+        if u.groups.count() < 1:
+            u.groups.add(Group.objects.get(name='admin'))
+            u.save()
+
+
+class Migration(migrations.Migration):
+    dependencies = [
+        ('cookbook', '0035_auto_20200427_1637'),
+    ]
+
+    operations = [
+        migrations.RunPython(apply_migration)
+    ]