$ git clone -n https://src.fedoraproject.org/rpms/sagemath.git /var/lib/mock/f33-build-354225-60095/root/chroot_tmpdir/scmroot/sagemath
Cloning into '/var/lib/mock/f33-build-354225-60095/root/chroot_tmpdir/scmroot/sagemath'...
$ git reset --hard de0ac7db5fba400ac0381bd7c598adaca3251001
HEAD is now at de0ac7d Actually remember to bump the Release field.