$ git clone -n https://src.fedoraproject.org/rpms/python-fastjsonschema.git /var/lib/mock/f40-build-2231151-53258/root/chroot_tmpdir/scmroot/python-fastjsonschema
Cloning into '/var/lib/mock/f40-build-2231151-53258/root/chroot_tmpdir/scmroot/python-fastjsonschema'...
$ git fetch origin 276919b2abffd035353fd0cbc7c65cf4cb5fb19d:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/python-fastjsonschema
 * [new ref]         276919b2abffd035353fd0cbc7c65cf4cb5fb19d -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 276919b Update to 2.18.0