[neutron] Is a provider of the "router" extension required also to provide the "extraroute" extension?

Hi Neutrinos - Calico's plugin has recently started failing CI, at the point where devstack initial network creation does "openstack router create ...", with the classic error "'NoneType' object is not iterable" [1], and I think this is because openstackclient assumes [2] that the returned router dict will always have a 'routes' field. If my analysis is correct, is that a correct assumption, or should openstackclient be more forgiving here? [1] https://openstack.fortnebula.com:13808/v1/AUTH_e8fd161dc34c421a979a9e6421f82... [2] https://opendev.org/openstack/python-openstackclient/src/branch/master/opens... Many thanks, Neil