Comment 38 for bug 1894843

@Corey the following patch (from upstream stable/queens) is not present in Ubuntu neutron package 2:12.1.1-0ubuntu4~cloud0
https://review.opendev.org/c/openstack/neutron/+/709406
This resulted in failure of few unit tests on ubuntu neutron package.

The unittests can also be resolved by adding the below line after https://opendev.org/openstack/neutron/src/branch/stable/queens/neutron/agent/l3/dvr_edge_router.py#L188

--- a/neutron/agent/l3/dvr_edge_router.py
+++ b/neutron/agent/l3/dvr_edge_router.py
@@ -186,6 +186,7 @@ class DvrEdgeRouter(dvr_local_router.DvrLocalRouter):
         # is to move the creation of the snat namespace here
         if self._is_this_snat_host():
             self.snat_namespace.create()
+ return self.snat_namespace

Please suggest if we need to SRU https://review.opendev.org/c/openstack/neutron/+/709406 in ubuntu neutron package or just update the debdiff with single line of code change