diff --git a/neutron_tempest_plugin/api/test_dhcp_ipv6.py b/neutron_tempest_plugin/api/test_dhcp_ipv6.py
index 3a7db96..69b4ea0 100644
--- a/neutron_tempest_plugin/api/test_dhcp_ipv6.py
+++ b/neutron_tempest_plugin/api/test_dhcp_ipv6.py
@@ -50,8 +50,8 @@
     def _remove_from_list_by_index(self, things_list, elem):
         for index, i in enumerate(things_list):
             if i['id'] == elem['id']:
-                break
-        del things_list[index]
+                del things_list[index]
+                return
 
     def _clean_network(self):
         body = self.client.list_ports()
diff --git a/neutron_tempest_plugin/api/test_qos.py b/neutron_tempest_plugin/api/test_qos.py
index ba7aad8..d31eab8 100644
--- a/neutron_tempest_plugin/api/test_qos.py
+++ b/neutron_tempest_plugin/api/test_qos.py
@@ -585,7 +585,7 @@
 
 
 class QosBandwidthLimitRuleWithDirectionTestJSON(
-    QosBandwidthLimitRuleTestJSON):
+        QosBandwidthLimitRuleTestJSON):
 
     required_extensions = (
         QosBandwidthLimitRuleTestJSON.required_extensions +
diff --git a/neutron_tempest_plugin/api/test_timestamp.py b/neutron_tempest_plugin/api/test_timestamp.py
index 4d2d32a..769d7cc 100644
--- a/neutron_tempest_plugin/api/test_timestamp.py
+++ b/neutron_tempest_plugin/api/test_timestamp.py
@@ -27,7 +27,7 @@
 
     required_extensions = ["standard-attr-timestamp"]
 
-    ## attributes for subnetpool
+    # attributes for subnetpool
     min_prefixlen = '28'
     max_prefixlen = '31'
     _ip_version = 4
diff --git a/tox.ini b/tox.ini
index c16664d..06eda94 100644
--- a/tox.ini
+++ b/tox.ini
@@ -44,14 +44,11 @@
 # H404 multi line docstring should start with a summary
 # H405 multi line docstring summary not separated with an empty line
 # N530 direct neutron imports not allowed
-# TODO(ihrachys) figure out what to do with N534 and N536
-# N534 Untranslated exception message
-# N536 Use assertIsNone rather than assertEqual to check for None values
-ignore = E125,E126,E128,E129,E265,H404,H405,N530,N534,N536
+ignore = E125,E126,E128,E129,E265,H404,H405,N530
 # H106: Don't put vim configuration in source files
 # H203: Use assertIs(Not)None to check for None
 # H904: Delay string interpolations at logging calls
-enable-extensions=H106,H203,H904
+enable-extensions = H106,H203,H904
 show-source = true
-exclude = ./.*,build,dist,doc
+exclude = ./.*,build,dist,doc,*egg*,releasenotes
 import-order-style = pep8