Build failed.

- release-openstack-python https://zuul.opendev.org/t/openstack/build/409054078b004e91911ad3954e203d5d : SUCCESS in 4m 48s
- announce-release https://zuul.opendev.org/t/openstack/build/960e057d51fc4eb08d0abb02bd864a37 : FAILURE in 7m 04s
- propose-update-constraints https://zuul.opendev.org/t/openstack/build/b390fec90060452e897b8ce175b1c841 : SUCCESS in 6m 40s

Sending the release announcement email failed. This appears to be due to a transient network issue:

OSError: [Errno 101] Network is unreachable