Setup deleted account

Pour pouvoir supprimer un compte, on crée un compte dummy qui a pour but
de recevoir les objets non supprimables (caisses, transferts/opérations
pour statistiques, etc.). Lors de la délétion d'un compte, tout est
transféré sur le dummy, qui est créé via migration.

kfet/migrations/0067_deleted_account.py

@@ -0,0 +1,32 @@
+# Generated by Django 2.2 on 2019-05-23 13:54
+
+from django.db import migrations, models
+
+from kfet import KFET_DELETED_TRIGRAMME, KFET_DELETED_USERNAME
+
+
+def setup_kfet_deleted_user(apps, schema_editor):
+    """
+    Setup models instances for the kfet deleted account.
+
+    Username and trigramme are retrieved from kfet.__init__ module.
+    Other data are registered here.
+    """
+    User = apps.get_model("auth", "User")
+    CofProfile = apps.get_model("gestioncof", "CofProfile")
+    Account = apps.get_model("kfet", "Account")
+
+    user, _ = User.objects.update_or_create(
+        username=KFET_DELETED_USERNAME, defaults={"first_name": "Compte K-Fêt supprimé"}
+    )
+    profile, _ = CofProfile.objects.update_or_create(user=user)
+    account, _ = Account.objects.update_or_create(
+        cofprofile=profile, defaults={"trigramme": KFET_DELETED_TRIGRAMME}
+    )
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [("kfet", "0066_on_delete_actions")]
+
+    operations = [migrations.RunPython(setup_kfet_deleted_user)]