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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 parse_args(arglist=None):
 """Parse cmd line arguments. Update :attr:`stagpy.conf` accordingly. Args: arglist (list of str):
 the list of cmd line arguments. If set to None, the arguments are taken from :attr:`sys.argv`. Returns: function: the function implementing the sub command to be executed. """

    climan = CLIManager(conf, **SUB_CMDS)

    create_complete_files(climan, CONFIG_DIR, 'stagpy', 'stagpy-git',
                          zsh_sourceable=True)

    cmd_args, all_subs = climan.parse_args(arglist)
    sub_cmd = cmd_args.loam_sub_name

    if sub_cmd is None:
        return cmd_args.func

    if sub_cmd != 'config':
        commands.report_parsing_problems(PARSING_OUT)

    if conf.common.set:
        set_conf_str(conf, conf.common.set)

    if conf.common.config:
        commands.config_pp(all_subs)

    load_mplstyle()

    try:
        _steps_to_slices()
    except AttributeError:
        pass
    return cmd_args.func