$ git clone -n https://github.com/xcp-ng-rpms/python3 /var/lib/mock/v8.3-incoming-10647-29201/root/chroot_tmpdir/scmroot/python3
Cloning into '/var/lib/mock/v8.3-incoming-10647-29201/root/chroot_tmpdir/scmroot/python3'...
$ git fetch origin 100a9ae475e29a267adef3f4004827de08dfa745:KOJI_FETCH_HEAD
From https://github.com/xcp-ng-rpms/python3
 * [new ref]         100a9ae475e29a267adef3f4004827de08dfa745 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 100a9ae Merge pull request #1 from xcp-ng-rpms/pcoval/review/master