$ git clone -n https://src.fedoraproject.org/rpms/duplicity.git /var/lib/mock/f40-build-796742-140845/root/chroot_tmpdir/scmroot/duplicity
Cloning into '/var/lib/mock/f40-build-796742-140845/root/chroot_tmpdir/scmroot/duplicity'...
$ git fetch origin 37c0318bea64ecfc9cdbc9c7fb1fe30adeb5a8ce:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/duplicity
 * [new ref]         37c0318bea64ecfc9cdbc9c7fb1fe30adeb5a8ce -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 37c0318 sources