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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 _click_autocomplete(root, text):
 """Completer generator for click applications."""

    try:
        parts = shlex.split(text)
    except ValueError:
        raise StopIteration

    location, incomplete = _click_resolve_command(root, parts)

    if not text.endswith(' ') and not incomplete and text:
        raise StopIteration

    if incomplete and not incomplete[0:2].isalnum():
        for param in location.params:
            if not isinstance(param, click.Option):
                continue
            for opt in itertools.chain(param.opts, param.secondary_opts):
                if opt.startswith(incomplete):
                    yield completion.Completion(opt, -len(incomplete), display_meta=param.help)

    elif isinstance(location, (click.MultiCommand, click.core.Group)):
        ctx = click.Context(location)
        commands = location.list_commands(ctx)
        for command in commands:
            if command.startswith(incomplete):
                cmd = location.get_command(ctx, command)
                yield completion.Completion(command, -len(incomplete), display_meta=cmd.short_help)