$ git clone -n https://src.fedoraproject.org/rpms/python-greenlet.git /var/lib/mock/f40-build-731383-103859/root/chroot_tmpdir/scmroot/python-greenlet
Cloning into '/var/lib/mock/f40-build-731383-103859/root/chroot_tmpdir/scmroot/python-greenlet'...
$ git fetch origin 9b0b4910914d582e42fa22afc9da420369f64c5b:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/python-greenlet
 * [new ref]         9b0b4910914d582e42fa22afc9da420369f64c5b -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 9b0b491 3.0.0