diff --git a/lemur/plugins/lemur_acme/tests/test_acme.py b/lemur/plugins/lemur_acme/tests/test_acme.py
index 58857b75..b66e6d58 100644
--- a/lemur/plugins/lemur_acme/tests/test_acme.py
+++ b/lemur/plugins/lemur_acme/tests/test_acme.py
@@ -421,7 +421,8 @@ class TestAcme(unittest.TestCase):
     @patch("lemur.extensions.metrics")
     def test_wait_for_dns_change(self, mock_metrics, mock_current_app):
         ultradns._has_dns_propagated = Mock(return_value=True)
-        ultradns.get_authoritative_nameserver = Mock(return_value="0.0.0.0")
+        nameserver = "0.0.0.0"
+        ultradns.get_authoritative_nameserver = Mock(return_value=nameserver)
         mock_metrics.send = Mock()
         domain = "_acme-challenge.test.example.com"
         token = "ABCDEFGHIJ"