agent config import error

eg. http://logs.openstack.org/10/438610/8/check/gate-networking-midonet-python27-ubuntu-xenial/193db3f/console.html

2017-03-17 12:02:45.258788 | --- import errors ---
2017-03-17 12:02:45.258820 | Failed to import test module: midonet.neutron.tests.unit.agent.test_interface
2017-03-17 12:02:45.258836 | Traceback (most recent call last):
2017-03-17 12:02:45.258882 | File "/home/jenkins/workspace/gate-networking-midonet-python27-ubuntu-xenial/.tox/py27/local/lib/python2.7/site-packages/unittest2/loader.py", line 456, in _find_test_path
2017-03-17 12:02:45.258901 | module = self._get_module_from_name(name)
2017-03-17 12:02:45.258947 | File "/home/jenkins/workspace/gate-networking-midonet-python27-ubuntu-xenial/.tox/py27/local/lib/python2.7/site-packages/unittest2/loader.py", line 395, in _get_module_from_name
2017-03-17 12:02:45.258960 | __import__(name)
2017-03-17 12:02:45.258984 | File "midonet/neutron/tests/unit/agent/test_interface.py", line 19, in <module>
2017-03-17 12:02:45.259000 | from neutron.agent.common import config
2017-03-17 12:02:45.259015 | ImportError: cannot import name config
2017-03-17 12:02:45.259031 | The test run didn't actually run any tests