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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 completion_hints(config, prompt, session, context, current, arguments):
 # type: (CompletionInfo, str, ShellSession, BundleContext, str, List[str]) -> List[str] """ Returns the possible completions of the current argument :param config: Configuration of the current completion :param prompt: The shell prompt string :param session: Current shell session :param context: Context of the shell UI bundle :param current: Current argument (to be completed) :param arguments: List of all arguments in their current state :return: A list of possible completions """

    if not current:
        # No word yet, so the current position is after the existing ones
        arg_idx = len(arguments)
    else:
        # Find the current word position
        arg_idx = arguments.index(current)

    # Find the ID of the next completer
    completers = config.completers
    if arg_idx > len(completers) - 1:
        # Argument is too far to be positional, try
        if config.multiple:
            # Multiple calls allowed for the last completer
            completer_id = completers[-1]
        else:
            # Nothing to return
            return []
    else:
        completer_id = completers[arg_idx]

    if completer_id == DUMMY:
        # Dummy completer: do nothing
        return []

    # Find the matching service
    svc_ref = context.get_service_reference(
        SVC_COMPLETER, "({}={})".format(PROP_COMPLETER_ID, completer_id)
    )
    if svc_ref is None:
        # Handler not found
        _logger.debug("Unknown shell completer ID: %s", completer_id)
        return []

    # Call the completer
    try:
        with use_service(context, svc_ref) as completer:
            matches = completer.complete(
                config, prompt, session, context, arguments, current
            )
            if not matches:
                return []

            return matches
    except Exception as ex:
        _logger.exception("Error calling completer %s: %s", completer_id, ex)
        return []