def get_cluster_range(hsp_list):
    """Take a list of SearchIO HSP objects an return a range from the furthest
    5' hsp end to the furthest 3' hsp end.
    """
    start = min([x.hit_range[0] for x in hsp_list])
    end = max([x.hit_range[1] for x in hsp_list])
    assert start < end
    return [start, end]