[Update] 修改assets 的related

apps/assets/migrations/0030_auto_20190619_1135.py

+# Generated by Django 2.1.7 on 2019-06-19 03:35
+
+from django.db import migrations, models
+import django.db.models.deletion
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('assets', '0029_auto_20190522_1114'),
+    ]
+
+    operations = [
+        migrations.AlterField(
+            model_name='asset',
+            name='admin_user',
+            field=models.ForeignKey(null=True, on_delete=django.db.models.deletion.PROTECT, related_name='assets', to='assets.AdminUser', verbose_name='Admin user'),
+        ),
+    ]