Resolve "Remove token-based filenames for generated PDF files"

Closes #449 (closed)

aleksis/core/migrations/0014_alter_pdffile_file.py

 # Generated by Django 3.2 on 2021-04-17 18:47
 
-import aleksis.core.models
 from django.db import migrations, models
 
+def _get_upload_path(instance, filename):  # noqa
+    return f"pdfs/{instance.secret}.pdf"
+
 
 class Migration(migrations.Migration):
 
@@ -14,6 +16,6 @@ class Migration(migrations.Migration):
         migrations.AlterField(
             model_name='pdffile',
             name='file',
-            field=models.FileField(blank=True, null=True, upload_to=aleksis.core.models.PDFFile._get_upload_path, verbose_name='Generated PDF file'),
+            field=models.FileField(blank=True, null=True, upload_to=_get_upload_path, verbose_name='Generated PDF file'),
         ),
     ]