diff --git a/river/proba/test_gaussian.py b/river/proba/test_gaussian.py
index f38fd4ff19..bb445cea16 100644
--- a/river/proba/test_gaussian.py
+++ b/river/proba/test_gaussian.py
@@ -1,7 +1,11 @@
-import pytest
-import pandas as pd
-import numpy as np
+from __future__ import annotations
+
 import math
+
+import numpy as np
+import pandas as pd
+import pytest
+
 from river import proba