better file display

fet2020/finance/models.py

@@ -1,3 +1,5 @@
+from pathlib import Path
+
 from django.core.validators import FileExtensionValidator, ValidationError
 from django.db import models
 from django.urls import reverse
@@ -221,3 +223,6 @@ class Bill(models.Model):
     def clean(self):
         if self.status is None:
             self.status = Bill.Status.SUBMITTED
+
+    def filename(self):
+        return Path(self.file_field.name).name