[Openstack-stable-maint] Stable check of openstack/tooz for ref refs/heads/stable/train failed

Build failed. - openstack-tox-docs https://zuul.opendev.org/t/openstack/build/43f4c501a1e74f5dbc79279c9097bec0 : SUCCESS in 5m 03s - openstack-tox-py27 https://zuul.opendev.org/t/openstack/build/dabc534d446244efa7852316f6c55d9f : FAILURE in 3m 36s - openstack-tox-py36 https://zuul.opendev.org/t/openstack/build/e0a8d6564d6a44fc98f4ffd37c52e3b4 : FAILURE in 5m 06s - openstack-tox-py37 https://zuul.opendev.org/t/openstack/build/e6a77280dfca4e7896202ad78ba1aed8 : FAILURE in 4m 22s