$ git clone -n https://src.fedoraproject.org/rpms/python-nbclient.git /var/lib/mock/f40-build-2167946-50976/root/chroot_tmpdir/scmroot/python-nbclient
Cloning into '/var/lib/mock/f40-build-2167946-50976/root/chroot_tmpdir/scmroot/python-nbclient'...
$ git fetch origin 5aaf189e73d720f1f88af0a4c759152cb8ab7a97:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/python-nbclient
 * [new ref]         5aaf189e73d720f1f88af0a4c759152cb8ab7a97 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 5aaf189 Update to 0.9.0 (rhbz#2248561)