Fixed and improved locking implementations

src/pretix/base/migrations/0018_eventlock_token.py

@@ -0,0 +1,20 @@
+# -*- coding: utf-8 -*-
+from __future__ import unicode_literals
+
+from django.db import models, migrations
+import uuid
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('pretixbase', '0017_order_guest_locale'),
+    ]
+
+    operations = [
+        migrations.AddField(
+            model_name='eventlock',
+            name='token',
+            field=models.UUIDField(default=uuid.uuid4),
+        ),
+    ]