def METHOD_NAME(object, arg, value, args_dict):
    '''Translate various user argument values, for adding given ``object``.
    Modifies ``args_dict``.'''
    database_table = None
    try:
        database_table = database.__dict__[arg.capitalize()]._table
    except:
        pass
    if database_table:
        args_dict[arg] = translate_database_arg(database_table, arg, value)
        return
    if arg == 'global_prefs_file':
        args_dict['global_prefs'] = open(value).read()
        return
    if object.DatabaseObject == XAppVersion:
        # 'add app_version' accepts multiple '-exec_file's with
        # '-signature_file' applying to the most recent exec_file
        if arg == 'exec_file':
            global most_recent_exec_file
            most_recent_exec_file = value
            args_dict.setdefault('exec_files',[]).append(value)
            # since 'exec_file' (without 's') is required, set it to None so
            # that argument checker knows we got one; we'll delete it later.
            args_dict[arg] = None
            return
        if arg == 'signature_file':
            args_dict.setdefault('signature_files',{})[most_recent_exec_file] = value
            return
    if arg == 'cross_project_id':
        if not value:
            value = tools.make_uuid()
    args_dict[arg] = value