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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def setup_multiifo_combine_statmap(workflow, final_bg_file_list, out_dir, tags):
 """ Combine the multiifo statmap files into one background file """

    if tags is None:
        tags = []
    make_analysis_dir(out_dir)
    logging.info('Setting up multiifo combine statmap')

    cstat_exe = PyCBCMultiifoCombineStatmap(workflow.cp,
                                            'combine_statmap',
                                            ifos=workflow.ifos,
                                            tags=tags,
                                            out_dir=out_dir)

    ifolist = ' '.join(workflow.ifos)
    cluster_window = float(workflow.cp.get_opt_tags('combine_statmap',
                                                    'cluster-window',
                                                    tags))
    combine_statmap_node = cstat_exe.create_node(final_bg_file_list,
                                                 ifolist,
                                                 cluster_window,
                                                 tags)
    workflow.add_node(combine_statmap_node)
    return combine_statmap_node.output_file