Explicitly create 'lvem' and 'public' tags

gracedb/events/migrations/0025_explicitly_create_access_tags.py

+# -*- coding: utf-8 -*-
+# Generated by Django 1.11.14 on 2018-09-28 14:21:20
+from __future__ import unicode_literals
+
+from django.db import migrations
+
+# Create Tag instances for current list of "blessed" tags.
+# Based on current list in settings (26 Oct 2017)
+
+# List of tag names and display names
+TAGS = [
+    {'name': 'lvem', 'displayName': 'LV-EM'},
+    {'name': 'public', 'displayName': 'Public'},
+]
+
+def add_tags(apps, schema_editor):
+    Tag = apps.get_model('events', 'Tag')
+
+    # Create tags
+    for tag_dict in TAGS:
+        tag, created = Tag.objects.get_or_create(name=tag_dict['name'])
+        tag.displayName = tag_dict['displayName']
+        tag.save()
+
+# Note there is no reverse migration since we don't want to remove these tags,
+# because they existed already, at least in production.
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('events', '0024_add_labels'),
+    ]
+
+    operations = [
+        migrations.RunPython(add_tags, migrations.RunPython.noop),
+    ]