$ git clone -n https://src.fedoraproject.org/rpms/python-cython0.29.git /var/lib/mock/f40-build-731184-103685/root/chroot_tmpdir/scmroot/python-cython0.29
Cloning into '/var/lib/mock/f40-build-731184-103685/root/chroot_tmpdir/scmroot/python-cython0.29'...
$ git fetch origin b9fae0143341296f405299652f23cfe8439b21c0:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/python-cython0.29
 * [new ref]         b9fae0143341296f405299652f23cfe8439b21c0 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at b9fae01 Disable emacs-cython-mode