Add migration to add GroupMembership.created and updated

h/migrations/versions/9c0efdf762a6_add_user_group_created_and_updated_.py

@@ -0,0 +1,17 @@
+"""Add user_group.created and updated columns."""
+
+from alembic import op
+from sqlalchemy import Column, DateTime
+
+revision = "9c0efdf762a6"
+down_revision = "59f42b6a0cd9"
+
+
+def upgrade():
+    op.add_column("user_group", Column("created", DateTime, index=True))
+    op.add_column("user_group", Column("updated", DateTime, index=True))
+
+
+def downgrade():
+    op.drop_column("user_group", "updated")
+    op.drop_column("user_group", "created")