diff --git a/oslo_vmware/exceptions.py b/oslo_vmware/exceptions.py
index a7a9bcb2..96b6c56e 100644
--- a/oslo_vmware/exceptions.py
+++ b/oslo_vmware/exceptions.py
@@ -51,7 +51,8 @@ class VMwareDriverException(Exception):
     """
     msg_fmt = _("An unknown exception occurred.")
 
-    __str__ = lambda self: self.description
+    def __str__(self):
+        return self.description
 
     def __init__(self, message=None, details=None, **kwargs):
 
diff --git a/oslo_vmware/hacking/checks.py b/oslo_vmware/hacking/checks.py
index 8591d71d..9c0caddc 100644
--- a/oslo_vmware/hacking/checks.py
+++ b/oslo_vmware/hacking/checks.py
@@ -14,6 +14,8 @@
 
 import re
 
+from hacking import core
+
 
 _all_log_levels = {'critical', 'error', 'exception', 'info',
                    'warning', 'debug'}
@@ -28,6 +30,7 @@ _log_translation_hint = re.compile(
     })
 
 
+@core.flake8ext
 def no_translate_logs(logical_line, filename):
     """N537 - Don't translate logs.
 
@@ -46,7 +49,3 @@ def no_translate_logs(logical_line, filename):
     """
     if _log_translation_hint.match(logical_line):
         yield (0, "N537: Log messages should not be translated!")
-
-
-def factory(register):
-    register(no_translate_logs)
diff --git a/oslo_vmware/objects/datastore.py b/oslo_vmware/objects/datastore.py
index 7f2c34ce..56b85f08 100644
--- a/oslo_vmware/objects/datastore.py
+++ b/oslo_vmware/objects/datastore.py
@@ -445,8 +445,8 @@ class DatastoreURL(object):
                 httplib.CannotSendHeader) as excep:
             excep_msg = _("Error occurred while creating HTTP connection "
                           "to write to file with URL = %s.") % str(self)
-        LOG.exception(excep_msg)
-        raise exceptions.VimConnectionException(excep_msg, excep)
+            LOG.exception(excep_msg)
+            raise exceptions.VimConnectionException(excep_msg, excep)
 
     def get_transfer_ticket(self, session, method):
         client_factory = session.vim.client.factory
diff --git a/oslo_vmware/service.py b/oslo_vmware/service.py
index 7fba28bf..f61ce602 100644
--- a/oslo_vmware/service.py
+++ b/oslo_vmware/service.py
@@ -459,5 +459,6 @@ class SudsLogFilter(logging.Filter):
 
         return True
 
+
 # Set log filter to mask/truncate vCenter credentials in suds logs.
 suds.client.log.addFilter(SudsLogFilter())
diff --git a/oslo_vmware/tests/test_vim_util.py b/oslo_vmware/tests/test_vim_util.py
index 27fecaea..36d63751 100644
--- a/oslo_vmware/tests/test_vim_util.py
+++ b/oslo_vmware/tests/test_vim_util.py
@@ -102,11 +102,6 @@ class VimUtilTest(base.TestCase):
                                             'skip': False,
                                             'selectSet': [rp_to_rp_sel_spec,
                                                           rp_to_vm_sel_spec]},
-                               'cr_to_rp': {'type': 'ComputeResource',
-                                            'path': 'resourcePool',
-                                            'skip': False,
-                                            'selectSet': [rp_to_rp_sel_spec,
-                                                          rp_to_vm_sel_spec]},
                                'ccr_to_h': {'type': 'ClusterComputeResource',
                                             'path': 'host',
                                             'skip': False,
diff --git a/test-requirements.txt b/test-requirements.txt
index c4f7f31d..3c8beeb2 100644
--- a/test-requirements.txt
+++ b/test-requirements.txt
@@ -3,7 +3,7 @@
 # process, which may cause wedges in the gate later.
 
 # Hacking already pins down pep8, pyflakes and flake8
-hacking!=0.13.0,<0.14,>=0.12.0 # Apache-2.0
+hacking>=3.0,<3.1.0 # Apache-2.0
 
 fixtures>=3.0.0 # Apache-2.0/BSD
 mock>=2.0.0 # BSD
diff --git a/tox.ini b/tox.ini
index b13d3f8f..5fc2f94c 100644
--- a/tox.ini
+++ b/tox.ini
@@ -44,14 +44,18 @@ commands = {posargs}
 
 [flake8]
 show-source = True
-ignore = H405
+ignore = H405,W504
 exclude=.venv,.git,.tox,dist,doc,*lib/python*,*egg,build,__init__.py
 
 [hacking]
 import_exceptions =
   oslo_vmware.tests.base
   tests.base
-local-check-factory = oslo_vmware.hacking.checks.factory
+
+[flake8:local-plugins]
+extension =
+  N537 = checks:no_translate_logs
+paths = ./oslo_vmware/hacking
 
 [testenv:releasenotes]
 whitelist_externals = rm