Make user email addresses unique

bookwyrm/migrations/0050_auto_20201002_2156.py

@@ -0,0 +1,18 @@
+# Generated by Django 3.0.7 on 2020-10-02 21:56
+
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('bookwyrm', '0049_passwordreset'),
+    ]
+
+    operations = [
+        migrations.AlterField(
+            model_name='user',
+            name='email',
+            field=models.EmailField(max_length=254, unique=True),
+        ),
+    ]