How to use the argcomplete.my_shlex.shlex function in argcomplete

def split_line(line, point=None):
    if point is None:
        point = len(line)
    lexer = shlex.shlex(line, posix=True)
    lexer.whitespace_split = True
    lexer.wordbreaks = os.environ.get("_ARGCOMPLETE_COMP_WORDBREAKS", "")
    words = []

    def split_word(word):
        # TODO: make this less ugly
        point_in_word = len(word) + point - lexer.instream.tell()
        if isinstance(lexer.state, (str, bytes)) and lexer.state in lexer.whitespace:
            point_in_word += 1
        if point_in_word > len(word):
            debug("In trailing whitespace")
            words.append(word)
            word = ""
        prefix, suffix = word[:point_in_word], word[point_in_word:]
        prequote = ""
        # posix