diff --git a/src/nc_time_axis/tests/unit/test_CFTimeFormatter.py b/src/nc_time_axis/tests/unit/test_CFTimeFormatter.py
index 0ab2818..657be40 100644
--- a/src/nc_time_axis/tests/unit/test_CFTimeFormatter.py
+++ b/src/nc_time_axis/tests/unit/test_CFTimeFormatter.py
@@ -1,4 +1,5 @@
 """Unit tests for the `nc_time_axis.CFTimeFormatter` class."""
+
 import pytest
 
 from nc_time_axis import CFTimeFormatter
diff --git a/src/nc_time_axis/tests/unit/test_NetCDFTimeDateLocator.py b/src/nc_time_axis/tests/unit/test_NetCDFTimeDateLocator.py
index b29b7de..8de09bd 100644
--- a/src/nc_time_axis/tests/unit/test_NetCDFTimeDateLocator.py
+++ b/src/nc_time_axis/tests/unit/test_NetCDFTimeDateLocator.py
@@ -1,6 +1,5 @@
 """Unit tests for the `nc-time-axis.NetCDFTimeDateLocator` class."""
 
-
 import unittest
 
 import cftime