import error on novadocker virt driver

2017-02-05 06:23:13.473598 | Failed to import test module: novadocker.tests.virt.docker.test_opencontrail
2017-02-05 06:23:13.473611 | Traceback (most recent call last):
2017-02-05 06:23:13.473652 | File "/home/jenkins/workspace/gate-nova-docker-python27-ubuntu-xenial/.tox/py27/local/lib/python2.7/site-packages/unittest2/loader.py", line 456, in _find_test_path
2017-02-05 06:23:13.473668 | module = self._get_module_from_name(name)
2017-02-05 06:23:13.473712 | File "/home/jenkins/workspace/gate-nova-docker-python27-ubuntu-xenial/.tox/py27/local/lib/python2.7/site-packages/unittest2/loader.py", line 395, in _get_module_from_name
2017-02-05 06:23:13.473722 | __import__(name)
2017-02-05 06:23:13.473745 | File "novadocker/tests/virt/docker/test_opencontrail.py", line 19, in <module>
2017-02-05 06:23:13.473767 | from novadocker.virt.docker import driver as docker_driver
2017-02-05 06:23:13.473786 | File "novadocker/virt/docker/__init__.py", line 20, in <module>
2017-02-05 06:23:13.473802 | from novadocker.virt.docker import driver
2017-02-05 06:23:13.473821 | File "novadocker/virt/docker/driver.py", line 37, in <module>
2017-02-05 06:23:13.473833 | from nova.compute import arch
2017-02-05 06:23:13.473850 | ImportError: cannot import name arch