$ git clone -n https://src.fedoraproject.org/rpms/python3.9.git /var/lib/mock/f42-build-side-1-3523527-46210/root/chroot_tmpdir/scmroot/python3.9
Cloning into '/var/lib/mock/f42-build-side-1-3523527-46210/root/chroot_tmpdir/scmroot/python3.9'...
$ git fetch origin d5085b58ccf5b13f7e69aa5a6af25c1c489b74d5:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/python3.9
 * [new ref]         d5085b58ccf5b13f7e69aa5a6af25c1c489b74d5 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at d5085b5 Regenerate patches with updated importpatches script