diff --git a/modoboa/admin/lib.py b/modoboa/admin/lib.py
index 9991d6110..a8aabd51d 100644
--- a/modoboa/admin/lib.py
+++ b/modoboa/admin/lib.py
@@ -198,23 +198,24 @@ def get_domain_mx_list(domain):
                     omit_final_dot=True, idna_codec=IDNA_2008_UTS_46)
                 ip_answers = dns.resolver.query(mx_domain)
             except dns.resolver.NXDOMAIN as e:
-                logger.error(_("No DNS records found without MX for %s") % domain, exc_info=e)
+                logger.error(_("No DNS records found without MX for %s")
+                             % domain, exc_info=e)
             else:
                 for ip_answer in ip_answers:
                     for answer_set in ip_answer.response.answer:
                         for address in answer_set:
                             try:
-                                mx_ip = ipaddress.ip_address(smart_text(address))
+                                address_smart = smart_text(address)
+                                mx_ip = ipaddress.ip_address(address_smart)
                             except ValueError as e:
                                 logger.warning(
-                                    _("Invalid IP address format for %(domain)s; "
-                                      "%(addr)s")
+                                    _("Invalid IP address format for "
+                                      "%(domain)s; %(addr)s")
                                     % {"domain": mx_domain,
                                        "addr": smart_text(address)},
                                     exc_info=e)
                             else:
-                                result.append((mx_domain, mx_ip))                    
-                        
+                                result.append((mx_domain, mx_ip))
     return result
 
 
diff --git a/modoboa/admin/tests/test_mx.py b/modoboa/admin/tests/test_mx.py
index 239aa7c43..b7bdc962f 100644
--- a/modoboa/admin/tests/test_mx.py
+++ b/modoboa/admin/tests/test_mx.py
@@ -117,12 +117,11 @@ class MXTestCase(ModoTestCase):
         self.set_global_parameter("use_specific_dns_server", "123.45.67.89")
         get_domain_mx_list("does-not-exist.example.com")
 
-    #@mock.patch("socket.getaddrinfo")
     @mock.patch("ipaddress.ip_address")
     @mock.patch.object(dns.resolver.Resolver, "query")
     def test_get_domain_mx_list_logging(self, mock_query, mock_ip_address):
+        """Test to get error loggins from specific DNS server."""
         mock_query.side_effect = utils.mock_dns_query_result
-        #mock_getaddrinfo.side_effect = utils.mock_ip_query_result
         mock_ip_address.side_effect = utils.mock_ip_address_result
         with LogCapture("modoboa.admin") as log:
             get_domain_mx_list("does-not-exist.example.com")
@@ -142,11 +141,11 @@ class MXTestCase(ModoTestCase):
                 _("DNS resolution timeout, unable to query %s at the moment")
                 % "timeout.example.com"),
             ("modoboa.admin", "ERROR",
-                _("No DNS records found without MX for %(domain)s")
-                % {"domain": "no-lookup.example.com"}),
+            _("No DNS records found without MX for %(domain)s")
+             % {"domain": "no-lookup.example.com"}),
             ("modoboa.admin", "WARNING",
-                _("Invalid IP address format for %(domain)s; %(addr)s")
-                % {"domain": "bad-response.example.com", "addr": "000.0.0.0"}),
+            _("Invalid IP address format for %(domain)s; %(addr)s")
+            % {"domain": "bad-response.example.com", "addr": "000.0.0.0"}),
         )