def METHOD_NAME(workflow, psd_files, out_dir, tags=None,
                     output_fmt='.txt'):
    make_analysis_dir(out_dir)
    tags = [] if tags is None else tags
    node = AvgPSDExecutable(workflow.cp, 'average_psd', ifos=workflow.ifos,
                            out_dir=out_dir, tags=tags).create_node()
    node.add_input_list_opt('--input-files', psd_files)
    if len(workflow.ifos) > 1:
        node.new_output_file_opt(workflow.analysis_time, output_fmt,
                                 '--detector-avg-file')
    node.new_multiifo_output_list_opt('--time-avg-file', workflow.ifos,
                                 workflow.analysis_time, output_fmt, tags=tags)
    workflow += node
    return node.output_files