How to use the configargparse.YAMLConfigFileParser function in ConfigArgParse

def get_parser():
    parser = configargparse.ArgumentParser(
        description="TTS Decode",
        config_file_parser_class=configargparse.YAMLConfigFileParser,
        formatter_class=configargparse.ArgumentDefaultsHelpFormatter,
    )

    # Note(kamo): Use '_' instead of '-' as separator.
    # '-' is confusing if written in yaml.
    parser.add_argument(
        "--config", is_config_file=True, help="config file path"
    )

    parser.add_argument(
        "--log_level",
        type=lambda x: x.upper(),
        default="INFO",
        choices=("INFO", "ERROR", "WARNING", "INFO", "DEBUG", "NOTSET"),
        help="The verbose level of logging",
    )

def get_parser():
    parser = configargparse.ArgumentParser(
        description='Transcribe text from speech using a speech recognition model on one CPU or GPU',
        config_file_parser_class=configargparse.YAMLConfigFileParser,
        formatter_class=configargparse.ArgumentDefaultsHelpFormatter)
    # general configuration
    parser.add('--config', is_config_file=True,
               help='Config file path')
    parser.add('--config2', is_config_file=True,
               help='Second config file path that overwrites the settings in `--config`')
    parser.add('--config3', is_config_file=True,
               help='Third config file path that overwrites the settings in `--config` and `--config2`')
    parser.add_argument('--ngpu', default=0, type=int,
                        help='Number of GPUs')
    parser.add_argument('--backend', default='pytorch', type=str,
                        choices=['pytorch'],
                        help='Backend library')
    parser.add_argument('--debugmode', default=1, type=int,
                        help='Debugmode')
    parser.add_argument('--seed', default=1, type=int,

def arg_conf(description):
    '''
    Reading argument given to the script.
    '''
    parser = configargparse.ArgParser(
        default_config_files=[
            '/etc/%s.yml' % __SCRIPT__,
            '~/%s.yml' % __SCRIPT__,
            './%s.yml' % __SCRIPT__
        ],
        description=description,
        config_file_parser_class=YAMLConfigFileParser
    )
    parser.add(
        '-i', '--xml-file',
        dest='xml_file',
        type=str,
        required=True,
        help='Name of the xml file containing maintenance'
    )
    parser.add(
        '--log-level',
        type=str,
        dest='log_level',
        default='error',
        help='Choose log level in debug, info, warning, error, critical'
    )
    parser.add(

def get_parser():
    parser = configargparse.ArgumentParser(
        description="Calc perplexity",
        config_file_parser_class=configargparse.YAMLConfigFileParser,
        formatter_class=configargparse.ArgumentDefaultsHelpFormatter,
    )

    # Note(kamo): Use '_' instead of '-' as separator.
    # '-' is confusing if written in yaml.
    parser.add_argument(
        "--config", is_config_file=True, help="config file path"
    )

    parser.add_argument(
        "--log_level",
        type=lambda x: x.upper(),
        default="INFO",
        choices=("INFO", "ERROR", "WARNING", "INFO", "DEBUG", "NOTSET"),
        help="The verbose level of logging",
    )

def add_arguments(
        cls, parser: configargparse.ArgumentParser = None
    ) -> configargparse.ArgumentParser:
        assert check_argument_types()
        # NOTE(kamo): Use '_' instead of '-' to avoid confusion
        if parser is None:
            parser = configargparse.ArgumentParser(
                description="Train launguage model",
                config_file_parser_class=configargparse.YAMLConfigFileParser,
                formatter_class=configargparse.ArgumentDefaultsHelpFormatter,
            )

        AbsTask.add_arguments(parser)
        group = parser.add_argument_group(description="Task related")

        # NOTE(kamo): add_arguments(..., required=True) can't be used
        # to provide --print_config mode. Instead of it, do as
        required = parser.get_default("required")
        required += ["token_list"]

        group.add_argument(
            "--token_list",
            type=str_or_none,
            default=None,
            help="A text mapping int-id to token",

def get_parser(parser=None, required=True):
    """Get default arguments."""
    if parser is None:
        parser = configargparse.ArgumentParser(
            description="Train a neural machine translation (NMT) model on one CPU, one or multiple GPUs",
            config_file_parser_class=configargparse.YAMLConfigFileParser,
            formatter_class=configargparse.ArgumentDefaultsHelpFormatter)
    # general configuration
    parser.add('--config', is_config_file=True, help='config file path')
    parser.add('--config2', is_config_file=True,
               help='second config file path that overwrites the settings in `--config`.')
    parser.add('--config3', is_config_file=True,
               help='third config file path that overwrites the settings in `--config` and `--config2`.')

    parser.add_argument('--ngpu', default=None, type=int,
                        help='Number of GPUs. If not given, use all visible devices')
    parser.add_argument('--train-dtype', default="float32",
                        choices=["float16", "float32", "float64", "O0", "O1", "O2", "O3"],
                        help='Data type for training (only pytorch backend). '
                        'O0,O1,.. flags require apex. See https://nvidia.github.io/apex/amp.html#opt-levels')
    parser.add_argument('--backend', default='chainer', type=str,
                        choices=['chainer', 'pytorch'],

def get_parser():
    """Get default arguments."""
    parser = configargparse.ArgumentParser(
        description='Translate text from speech using a speech translation model on one CPU or GPU',
        config_file_parser_class=configargparse.YAMLConfigFileParser,
        formatter_class=configargparse.ArgumentDefaultsHelpFormatter)
    # general configuration
    parser.add('--config', is_config_file=True,
               help='Config file path')
    parser.add('--config2', is_config_file=True,
               help='Second config file path that overwrites the settings in `--config`')
    parser.add('--config3', is_config_file=True,
               help='Third config file path that overwrites the settings in `--config` and `--config2`')

    parser.add_argument('--ngpu', type=int, default=0,
                        help='Number of GPUs')
    parser.add_argument('--dtype', choices=("float16", "float32", "float64"), default="float32",
                        help='Float precision (only available in --api v2)')
    parser.add_argument('--backend', type=str, default='chainer',
                        choices=['chainer', 'pytorch'],
                        help='Backend library')

def __init__(self,
                 config_file_parser_class=configargparse.YAMLConfigFileParser,
                 formatter_class=configargparse.ArgumentDefaultsHelpFormatter,
                 **kwargs):
        """This funtion decides config parser and formatter
        
        Keyword Arguments:
            config_file_parser_class {configargparse.ConfigFileParser} -- config file parser (default: {configargparse.YAMLConfigFileParser})
            formatter_class {configargparse.ArgumentDefaultsHelpFormatter} -- config formatter (default: {configargparse.ArgumentDefaultsHelpFormatter})
        """
        
        self.parser = configargparse.ArgumentParser(
            config_file_parser_class=config_file_parser_class,
            formatter_class=formatter_class,
            **kwargs)

def add_arguments(cls, parser: configargparse.ArgumentParser = None) \
            -> configargparse.ArgumentParser:
        # Note(kamo): Use '_' instead of '-' to avoid confusion as separator
        if parser is None:
            parser = configargparse.ArgumentParser(
                description='',
                config_file_parser_class=configargparse.YAMLConfigFileParser,
                formatter_class=configargparse.ArgumentDefaultsHelpFormatter)
        BaseTask.add_arguments(parser)
        return parser

def get_parser(parser=None, required=True):
    """Get default arguments."""
    if parser is None:
        parser = configargparse.ArgumentParser(
            description="Train a speech translation (ST) model on one CPU, one or multiple GPUs",
            config_file_parser_class=configargparse.YAMLConfigFileParser,
            formatter_class=configargparse.ArgumentDefaultsHelpFormatter)
    # general configuration
    parser.add('--config', is_config_file=True, help='config file path')
    parser.add('--config2', is_config_file=True,
               help='second config file path that overwrites the settings in `--config`.')
    parser.add('--config3', is_config_file=True,
               help='third config file path that overwrites the settings in `--config` and `--config2`.')

    parser.add_argument('--ngpu', default=None, type=int,
                        help='Number of GPUs. If not given, use all visible devices')
    parser.add_argument('--train-dtype', default="float32",
                        choices=["float16", "float32", "float64", "O0", "O1", "O2", "O3"],
                        help='Data type for training (only pytorch backend). '
                        'O0,O1,.. flags require apex. See https://nvidia.github.io/apex/amp.html#opt-levels')
    parser.add_argument('--backend', default='chainer', type=str,
                        choices=['chainer', 'pytorch'],