UPD: more cool participant admin stuff.

dav_events/migrations/0031_auto_20190604_0658.py

@@ -0,0 +1,21 @@
+# -*- coding: utf-8 -*-
+# Generated by Django 1.11.20 on 2019-06-04 06:58
+from __future__ import unicode_literals
+
+import django.core.validators
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('dav_events', '0030_auto_20190603_1014'),
+    ]
+
+    operations = [
+        migrations.AlterField(
+            model_name='participant',
+            name='dav_number',
+            field=models.CharField(max_length=62, validators=[django.core.validators.RegexValidator('^([0-9]{1,10}/[0-9]{2,10}/)?[0-9]{1,10}(\\*[0-9]{1,10})?(\\*[0-9]{4}\\*[0-9]{4})?([* ][0-9]{8})?$', 'Ungültiges Format.')], verbose_name='DAV Mitgliednummer'),
+        ),
+    ]