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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 menuconfig(kconf):
 """ Launches the configuration interface, returning after the user exits. kconf: Kconfig instance to be configured """

    global _kconf
    global _conf_filename
    global _conf_changed
    global _minconf_filename
    global _show_all

    _kconf = kconf

    # Load existing configuration and set _conf_changed True if it is outdated
    _conf_changed = _load_config()

    # Filename to save configuration to
    _conf_filename = standard_config_filename()

    # Filename to save minimal configuration to
    _minconf_filename = "defconfig"

    # Any visible items in the top menu?
    _show_all = False
    if not _shown_nodes(kconf.top_node):
        # Nothing visible. Start in show-all mode and try again.
        _show_all = True
        if not _shown_nodes(kconf.top_node):
            # Give up. The implementation relies on always having a selected
            # node.
            print("Empty configuration -- nothing to configure.\n"
                  "Check that environment variables are set properly.")
            return

    # Disable warnings. They get mangled in curses mode, and we deal with
    # errors ourselves.
    kconf.disable_warnings()

    # Make curses use the locale settings specified in the environment
    locale.setlocale(locale.LC_ALL, "")

    # Try to fix Unicode issues on systems with bad defaults
    if _CONVERT_C_LC_CTYPE_TO_UTF8:
        _convert_c_lc_ctype_to_utf8()

    # Get rid of the delay between pressing ESC and jumping to the parent menu,
    # unless the user has set ESCDELAY (see ncurses(3)). This makes the UI much
    # smoother to work with.
    #
    # Note: This is strictly pretty iffy, since escape codes for e.g. cursor
    # keys start with ESC, but I've never seen it cause problems in practice
    # (probably because it's unlikely that the escape code for a key would get
    # split up across read()s, at least with a terminal emulator). Please
    # report if you run into issues. Some suitable small default value could be
    # used here instead in that case. Maybe it's silly to not put in the
    # smallest imperceptible delay here already, though I don't like guessing.
    #
    # (From a quick glance at the ncurses source code, ESCDELAY might only be
    # relevant for mouse events there, so maybe escapes are assumed to arrive
    # in one piece already...)
    os.environ.setdefault("ESCDELAY", "0")

    # Enter curses mode. _menuconfig() returns a string to print on exit, after
    # curses has been de-initialized.
    print(curses.wrapper(_menuconfig))