diff --git a/README.md b/README.md
index 66a3303..082e365 100644
--- a/README.md
+++ b/README.md
@@ -1,5 +1,7 @@
 # FSRS4Anki Helper
 
+[![Code style: black](https://img.shields.io/badge/code%20style-black-000000.svg)](https://github.com/psf/black)
+
 FSRS4Anki Helper is an Anki add-on that supports [FSRS4Anki](https://github.com/open-spaced-repetition/fsrs4anki) scheduler. It has six main features:
 
 - **Reschedule** cards based on their entire review histories.
diff --git a/browser/custom_columns.py b/browser/custom_columns.py
index 626dd41..34e4f6d 100644
--- a/browser/custom_columns.py
+++ b/browser/custom_columns.py
@@ -17,9 +17,9 @@ def on_browser_did_fetch_row(
         active_columns: Sequence[str],
     ) -> None:
         if (
-            index := active_columns.index(self.key)
-            if self.key in active_columns
-            else None
+            index := (
+                active_columns.index(self.key) if self.key in active_columns else None
+            )
         ) is None:
             return