diff --git a/tests/test_x509_ext.py b/tests/test_x509_ext.py
index d0f4cac..f7be4bb 100644
--- a/tests/test_x509_ext.py
+++ b/tests/test_x509_ext.py
@@ -165,6 +165,7 @@
         assert hash(invalid1) == hash(invalid2)
         assert hash(invalid1) != hash(invalid3)
 
+
 class TestNoticeReference(object):
     def test_notice_numbers_not_all_int(self):
         with pytest.raises(TypeError):