Fix lint

aleksis/apps/kort/models.py

@@ -156,10 +156,9 @@ class CardPrinter(ExtensibleModel):
             self.status
             not in (CardPrinterStatus.NOT_REGISTERED.value, CardPrinterStatus.OFFLINE.value)
             and self.last_seen_at
-        ):
-            if self.last_seen_at < timezone.now() - timedelta(minutes=1):
-                self.status = CardPrinterStatus.OFFLINE.value
-                self.save()
+        ) and self.last_seen_at < timezone.now() - timedelta(minutes=1):
+            self.status = CardPrinterStatus.OFFLINE.value
+            self.save()
 
     @classmethod
     def check_online_status_for_all(cls, qs=None):
@@ -263,7 +262,7 @@ class CardLayout(ExtensibleModel):
             t = Template(self.template)
             t.render(Context())
         except Exception as e:
-            raise ValidationError(_("Template is invalid: {}").format(e))
+            raise ValidationError(_("Template is invalid: {}").format(e)) from e
 
     def __str__(self):
         return self.name

aleksis/apps/kort/views.py

@@ -339,7 +339,7 @@ class CardLayoutFormMixin:
 
     def post(self, request, *args, **kwargs):
         self.object = self.get_object()
-        context = self.get_context_data(**kwargs)
+        self.get_context_data(**kwargs)
         form = self.get_form()
         if form.is_valid() and self.formset.is_valid():
             return self.form_valid(form)