diff --git a/pytorch_optimizer/optimizer/lookahead.py b/pytorch_optimizer/optimizer/lookahead.py
index 6f3be06da..6e149f0f4 100644
--- a/pytorch_optimizer/optimizer/lookahead.py
+++ b/pytorch_optimizer/optimizer/lookahead.py
@@ -60,7 +60,7 @@ def __init__(
     @property
     def param_groups(self):
         return self.optimizer.param_groups
-        
+
     def __getstate__(self):
         return {
             'state': self.state,