diff --git a/python_tests/test_api.py b/python_tests/test_api.py
index 2e46be43..d5de330d 100644
--- a/python_tests/test_api.py
+++ b/python_tests/test_api.py
@@ -8,8 +8,8 @@ from optuna import get_all_study_summaries
 from optuna.study import StudyDirection
 from optuna_dashboard._app import create_app
 from optuna_dashboard._app import create_new_study
-from optuna_dashboard._preferential_history import NewHistory
 from optuna_dashboard._preference_setting import register_preference_feedback_component_type
+from optuna_dashboard._preferential_history import NewHistory
 from optuna_dashboard._preferential_history import remove_history
 from optuna_dashboard._preferential_history import report_history
 from optuna_dashboard._serializer import serialize_preference_history