Add migrations and add wrapper func for path_and_rename

aleksis/apps/mensa/migrations/0001_initial.py

+# Generated by Django 3.0.2 on 2020-01-18 13:05
+
+import aleksis.apps.mensa.models
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    initial = True
+
+    dependencies = [
+    ]
+
+    operations = [
+        migrations.CreateModel(
+            name='Menu',
+            fields=[
+                ('id', models.AutoField(auto_created=True, primary_key=True, serialize=False, verbose_name='ID')),
+                ('calendar_week', models.IntegerField(verbose_name='CW')),
+                ('year', models.IntegerField(verbose_name='Year')),
+                ('pdf', models.FileField(upload_to=aleksis.apps.mensa.models.path_and_rename_menu, verbose_name='PDF')),
+            ],
+            options={
+                'verbose_name': 'Menu',
+                'verbose_name_plural': 'Menus',
+                'unique_together': {('calendar_week', 'year')},
+            },
+        ),
+    ]

aleksis/apps/mensa/models.py

@@ -5,10 +5,14 @@ from aleksis.core.util.core_helpers import path_and_rename
 from django.utils.translation import gettext_lazy as _
 
 
+def path_and_rename_menu(instance, filename: str) -> str:
+    return path_and_rename(instance, filename, upload_to="menu")
+
+
 class Menu(models.Model):
     calendar_week = models.IntegerField(verbose_name=_("CW"))
     year = models.IntegerField(verbose_name=_("Year"))
-    pdf = models.FileField(upload_to=lambda a, b: path_and_rename(a, b, upload_to="menu"), verbose_name=_("PDF"))
+    pdf = models.FileField(upload_to=path_and_rename_menu, verbose_name=_("PDF"))
 
     class Meta:
         unique_together = ("calendar_week", "year")