$ git clone -n https://src.fedoraproject.org/rpms/marshalparser.git /var/lib/mock/f40-build-2010063-45555/root/chroot_tmpdir/scmroot/marshalparser
Cloning into '/var/lib/mock/f40-build-2010063-45555/root/chroot_tmpdir/scmroot/marshalparser'...
$ git fetch origin ef94a7a1251da1f35f461efdfdb307f840d9a51d:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/marshalparser
 * [new ref]         ef94a7a1251da1f35f461efdfdb307f840d9a51d -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at ef94a7a Don't test with retired Python 3.7