[keystone][7.0] Periodic job fails on env built from packages

[Dmitry Teselkin]

Periodic job for openstack/keystone fails on env build from packages

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05:24:40 Captured traceback:
05:24:40 ~~~~~~~~~~~~~~~~~~~
05:24:40 Traceback (most recent call last):
05:24:40 File "keystone/tests/unit/test_hacking_checks.py", line 143, in test
05:24:40 self.assert_has_errors(code, expected_errors=errors)
05:24:40 File "keystone/tests/unit/test_hacking_checks.py", line 52, in assert_has_errors
05:24:40 actual_errors = [e[:3] for e in self.run_check(code)]
05:24:40 File "/usr/lib/python2.7/dist-packages/mock.py", line 1210, in patched
05:24:40 return func(*args, **keywargs)
05:24:40 File "keystone/tests/unit/test_hacking_checks.py", line 47, in run_check
05:24:40 checker.check_all()
05:24:40 File "/usr/lib/python2.7/dist-packages/pep8.py", line 1393, in check_all
05:24:40 self.check_logical()
05:24:40 File "/usr/lib/python2.7/dist-packages/pep8.py", line 1327, in check_logical
05:24:40 for result in self.run_check(check, argument_names):
05:24:40 File "/usr/lib/python2.7/dist-packages/pep8.py", line 1256, in run_check
05:24:40 arguments.append(getattr(self, name))
05:24:40 AttributeError: 'Checker' object has no attribute 'blank_before'
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Link to the logs: http://logs.mosi.mirantis.net/periodic-pkg/periodic-keystone-python27-pkg-mos70/0df1324
Jenkins job: https://jenkins.mosi.mirantis.net/job/periodic-keystone-python27-pkg-mos70/