diff --git a/qt/aqt/emptycards.py b/qt/aqt/emptycards.py
index 773d1c650..55b02fb6b 100644
--- a/qt/aqt/emptycards.py
+++ b/qt/aqt/emptycards.py
@@ -85,10 +85,10 @@ class EmptyCardsDialog(QDialog):
 
         self.mw.taskman.run_in_background(delete, on_done)
 
-    def _delete_cards(self, keep_notes):
+    def _delete_cards(self, keep_notes: bool) -> int:
         to_delete = []
+        note: NoteWithEmptyCards
         for note in self.report.notes:
-            note: NoteWithEmptyCards = note
             if keep_notes and note.will_delete_note:
                 # leave first card
                 to_delete.extend(note.card_ids[1:])
diff --git a/qt/mypy.ini b/qt/mypy.ini
index 04415f4cd..31cf898b2 100644
--- a/qt/mypy.ini
+++ b/qt/mypy.ini
@@ -92,3 +92,5 @@ check_untyped_defs=true
 check_untyped_defs=true
 [mypy-aqt.addons]
 check_untyped_defs=true
+[mypy-aqt.emptycards]
+check_untyped_defs=true