diff --git a/tests/optimize/conftest.py b/tests/optimize/conftest.py
index 4d257addc..cb8a6b5f7 100644
--- a/tests/optimize/conftest.py
+++ b/tests/optimize/conftest.py
@@ -30,7 +30,7 @@ def hyperopt_conf(default_conf):
 
 
 @pytest.fixture(autouse=True)
-def backtesting_cleanup() -> None:
+def backtesting_cleanup():
     yield None
 
     Backtesting.cleanup()