$ git clone -n https://src.fedoraproject.org/rpms/python-graph-tool.git /var/lib/mock/f40-build-775835-128459/root/chroot_tmpdir/scmroot/python-graph-tool
Cloning into '/var/lib/mock/f40-build-775835-128459/root/chroot_tmpdir/scmroot/python-graph-tool'...
$ git fetch origin 1aade9078a179c611d57da644149af3a0a0dd2c5:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/python-graph-tool
 * [new ref]         1aade9078a179c611d57da644149af3a0a0dd2c5 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 1aade90 Update to 2.59 (close RHBZ#2256970)