Format code with ruff to pass CI format check

src/tradefinder/strategies/supertrend.py

@@ -45,7 +45,9 @@ class SupertrendStrategy(Strategy):
             multiplier=float(self._multiplier),
         )
 
-        direction_col = next((col for col in supertrend.columns if col.startswith("SUPERTd_")), None)
+        direction_col = next(
+            (col for col in supertrend.columns if col.startswith("SUPERTd_")), None
+        )
         if direction_col is None:
             logger.debug("Supertrend direction series missing", strategy=self.name)
             return None
@@ -110,7 +112,11 @@ class SupertrendStrategy(Strategy):
 
     def get_stop_loss(self, entry_price: Decimal, side: Side) -> Decimal:
         """Use ATR buffer for Supertrend stop loss."""
-        atr_buffer = self._last_atr if self._last_atr and self._last_atr > Decimal("0") else entry_price * Decimal("0.02")
+        atr_buffer = (
+            self._last_atr
+            if self._last_atr and self._last_atr > Decimal("0")
+            else entry_price * Decimal("0.02")
+        )
         if side == Side.BUY:
             stop = entry_price - atr_buffer
         else:
@@ -150,7 +156,14 @@ class SupertrendStrategy(Strategy):
 
     @staticmethod
     def _trend_level(supertrend: pd.DataFrame) -> Decimal | None:
-        trend_col = next((col for col in supertrend.columns if col.startswith("SUPERT_") and not col.startswith("SUPERTd_")), None)
+        trend_col = next(
+            (
+                col
+                for col in supertrend.columns
+                if col.startswith("SUPERT_") and not col.startswith("SUPERTd_")
+            ),
+            None,
+        )
         if trend_col is None:
             return None
         return SupertrendStrategy._decimal_from_series_tail(supertrend[trend_col])