diff --git a/feature_extractors/feature_extractors.py b/feature_extractors/feature_extractors.py
index 2e0c8fa..66f3a23 100644
--- a/feature_extractors/feature_extractors.py
+++ b/feature_extractors/feature_extractors.py
@@ -4,7 +4,11 @@ from feature_extractors.utils import get_close_low_high
 
 
 def feature_debug_future_lookahead(df: pd.DataFrame, period: int) -> pd.Series:
-    return df["returns"].rolling(window=pd.api.indexers.FixedForwardWindowIndexer(window_size=period)).sum()
+    return (
+        df["returns"]
+        .rolling(window=pd.api.indexers.FixedForwardWindowIndexer(window_size=period))
+        .sum()
+    )
 
 
 def feature_lag(df: pd.DataFrame, period: int) -> pd.Series: