diff --git a/python/paddle/trainer_config_helpers/evaluators.py b/python/paddle/trainer_config_helpers/evaluators.py
index 15b573b48ead7fa255ad28f656fe1e2461a427c2..3e0e88972c58e8c853e79e21f839943ae4b027d6 100644
--- a/python/paddle/trainer_config_helpers/evaluators.py
+++ b/python/paddle/trainer_config_helpers/evaluators.py
@@ -330,8 +330,7 @@ def chunk_evaluator(
         label,
         chunk_scheme,
         num_chunk_types,
-        name=None,
-        ):
+        name=None, ):
     """
     Chunk evaluator is used to evaluate segment labelling accuracy for a
     sequence. It calculates the chunk detection F1 score.