$ git clone -n https://src.fedoraproject.org/rpms/python-qt5.git /var/lib/mock/f40-build-773005-126774/root/chroot_tmpdir/scmroot/python-qt5
Cloning into '/var/lib/mock/f40-build-773005-126774/root/chroot_tmpdir/scmroot/python-qt5'...
$ git fetch origin d7c6cef96c922ece967beab9582b5adbe7e19956:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/python-qt5
 * [new ref]         d7c6cef96c922ece967beab9582b5adbe7e19956 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at d7c6cef Rebuild (qt5)