$ git clone -n https://src.fedoraproject.org/rpms/python-pynn.git /var/lib/mock/f42-build-3442837-45457/root/chroot_tmpdir/scmroot/python-pynn
Cloning into '/var/lib/mock/f42-build-3442837-45457/root/chroot_tmpdir/scmroot/python-pynn'...
$ git fetch origin 18e01b0e416830d497687cebc09e080e22cb09c5:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/python-pynn
 * [new ref]         18e01b0e416830d497687cebc09e080e22cb09c5 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 18e01b0 Rebuild with gsl 2.8