Python argparse.Action() Examples

def test(self):

        def get_my_type(string):
            return 'my_type{%s}' % string

        parser = argparse.ArgumentParser()
        parser.register('type', 'my_type', get_my_type)
        parser.add_argument('-x', type='my_type')
        parser.add_argument('y', type='my_type')

        self.assertEqual(parser.parse_args('1'.split()),
                         NS(x=None, y='my_type{1}'))
        self.assertEqual(parser.parse_args('-x 1 42'.split()),
                         NS(x='my_type{1}', y='my_type{42}'))


# ============
# Action tests
# ============ 

def pytest_addoption(parser):
    group = parser.getgroup("sqlalchemy")

    def make_option(name, **kw):
        callback_ = kw.pop("callback", None)
        if callback_:
            class CallableAction(argparse.Action):
                def __call__(self, parser, namespace,
                             values, option_string=None):
                    callback_(option_string, values, parser)
            kw["action"] = CallableAction

        group.addoption(name, **kw)

    plugin_base.setup_options(make_option)
    plugin_base.read_config() 

def pytest_addoption(parser):
    """
    Option '--regression-full' needs to be used to run all regression tests,
    including the full-length xia2 runs.
    """

    class RFAction(argparse.Action):
        def __call__(self, parser, namespace, values, option_string):
            namespace.regression = True
            namespace.regression_full = True

    parser.addoption(
        "--regression-full",
        nargs=0,
        action=RFAction,
        help="run all regression tests, this will take a while. Implies --regression",
    ) 

def pytest_addoption(parser):
    group = parser.getgroup("sqlalchemy")

    def make_option(name, **kw):
        callback_ = kw.pop("callback", None)
        if callback_:
            class CallableAction(argparse.Action):
                def __call__(self, parser, namespace,
                             values, option_string=None):
                    callback_(option_string, values, parser)
            kw["action"] = CallableAction

        group.addoption(name, **kw)

    plugin_base.setup_options(make_option)
    plugin_base.read_config() 

def pytest_addoption(parser):
    group = parser.getgroup("sqlalchemy")

    def make_option(name, **kw):
        callback_ = kw.pop("callback", None)
        if callback_:
            class CallableAction(argparse.Action):
                def __call__(self, parser, namespace,
                             values, option_string=None):
                    callback_(option_string, values, parser)
            kw["action"] = CallableAction

        group.addoption(name, **kw)

    plugin_base.setup_options(make_option)
    plugin_base.read_config() 

def test(self):

        def get_my_type(string):
            return 'my_type{%s}' % string

        parser = argparse.ArgumentParser()
        parser.register('type', 'my_type', get_my_type)
        parser.add_argument('-x', type='my_type')
        parser.add_argument('y', type='my_type')

        self.assertEqual(parser.parse_args('1'.split()),
                         NS(x=None, y='my_type{1}'))
        self.assertEqual(parser.parse_args('-x 1 42'.split()),
                         NS(x='my_type{1}', y='my_type{42}'))


# ============
# Action tests
# ============ 

def cli_skip_missing_interpreter(parser):
    class SkipMissingInterpreterAction(argparse.Action):
        def __call__(self, parser, namespace, values, option_string=None):
            value = "true" if values is None else values
            if value not in ("config", "true", "false"):
                raise argparse.ArgumentTypeError("value must be config, true or false")
            setattr(namespace, self.dest, value)

    parser.add_argument(
        "-s",
        "--skip-missing-interpreters",
        default="config",
        metavar="val",
        nargs="?",
        action=SkipMissingInterpreterAction,
        help="don't fail tests for missing interpreters: {config,true,false} choice",
    ) 

def pytest_addoption(parser):
    group = parser.getgroup("sqlalchemy")

    def make_option(name, **kw):
        callback_ = kw.pop("callback", None)
        if callback_:
            class CallableAction(argparse.Action):
                def __call__(self, parser, namespace,
                             values, option_string=None):
                    callback_(option_string, values, parser)
            kw["action"] = CallableAction

        group.addoption(name, **kw)

    plugin_base.setup_options(make_option)
    plugin_base.read_config() 

def pytest_addoption(parser):
    group = parser.getgroup("sqlalchemy")

    def make_option(name, **kw):
        callback_ = kw.pop("callback", None)
        if callback_:
            class CallableAction(argparse.Action):
                def __call__(self, parser, namespace,
                             values, option_string=None):
                    callback_(option_string, values, parser)
            kw["action"] = CallableAction

        group.addoption(name, **kw)

    plugin_base.setup_options(make_option)
    plugin_base.read_config() 

def pytest_addoption(parser):
    group = parser.getgroup("sqlalchemy")

    def make_option(name, **kw):
        callback_ = kw.pop("callback", None)
        if callback_:
            class CallableAction(argparse.Action):
                def __call__(self, parser, namespace,
                             values, option_string=None):
                    callback_(option_string, values, parser)
            kw["action"] = CallableAction

        group.addoption(name, **kw)

    plugin_base.setup_options(make_option)
    plugin_base.read_config() 

def pytest_addoption(parser):
    group = parser.getgroup("sqlalchemy")

    def make_option(name, **kw):
        callback_ = kw.pop("callback", None)
        if callback_:
            class CallableAction(argparse.Action):
                def __call__(self, parser, namespace,
                             values, option_string=None):
                    callback_(option_string, values, parser)
            kw["action"] = CallableAction

        group.addoption(name, **kw)

    plugin_base.setup_options(make_option)
    plugin_base.read_config() 

def pytest_addoption(parser):
    group = parser.getgroup("sqlalchemy")

    def make_option(name, **kw):
        callback_ = kw.pop("callback", None)
        if callback_:
            class CallableAction(argparse.Action):
                def __call__(self, parser, namespace,
                             values, option_string=None):
                    callback_(option_string, values, parser)
            kw["action"] = CallableAction

        group.addoption(name, **kw)

    plugin_base.setup_options(make_option)
    plugin_base.read_config() 

def test(self):

        def get_my_type(string):
            return 'my_type{%s}' % string

        parser = argparse.ArgumentParser()
        parser.register('type', 'my_type', get_my_type)
        parser.add_argument('-x', type='my_type')
        parser.add_argument('y', type='my_type')

        self.assertEqual(parser.parse_args('1'.split()),
                         NS(x=None, y='my_type{1}'))
        self.assertEqual(parser.parse_args('-x 1 42'.split()),
                         NS(x='my_type{1}', y='my_type{42}'))


# ============
# Action tests
# ============ 

def pytest_addoption(parser):
    group = parser.getgroup("sqlalchemy")

    def make_option(name, **kw):
        callback_ = kw.pop("callback", None)
        if callback_:
            class CallableAction(argparse.Action):
                def __call__(self, parser, namespace,
                             values, option_string=None):
                    callback_(option_string, values, parser)
            kw["action"] = CallableAction

        group.addoption(name, **kw)

    plugin_base.setup_options(make_option)
    plugin_base.read_config() 

def pytest_addoption(parser):
    group = parser.getgroup("sqlalchemy")

    def make_option(name, **kw):
        callback_ = kw.pop("callback", None)
        if callback_:
            class CallableAction(argparse.Action):
                def __call__(self, parser, namespace,
                             values, option_string=None):
                    callback_(option_string, values, parser)
            kw["action"] = CallableAction

        group.addoption(name, **kw)

    plugin_base.setup_options(make_option)
    plugin_base.read_config() 

def pytest_addoption(parser):
    group = parser.getgroup("sqlalchemy")

    def make_option(name, **kw):
        callback_ = kw.pop("callback", None)
        if callback_:
            class CallableAction(argparse.Action):
                def __call__(self, parser, namespace,
                             values, option_string=None):
                    callback_(option_string, values, parser)
            kw["action"] = CallableAction

        group.addoption(name, **kw)

    plugin_base.setup_options(make_option)
    plugin_base.read_config() 

def test(self):

        def get_my_type(string):
            return 'my_type{%s}' % string

        parser = argparse.ArgumentParser()
        parser.register('type', 'my_type', get_my_type)
        parser.add_argument('-x', type='my_type')
        parser.add_argument('y', type='my_type')

        self.assertEqual(parser.parse_args('1'.split()),
                         NS(x=None, y='my_type{1}'))
        self.assertEqual(parser.parse_args('-x 1 42'.split()),
                         NS(x='my_type{1}', y='my_type{42}'))


# ============
# Action tests
# ============ 

def get_argparse_extension_checker(choices, dir_allowed=False):
    """Get an :class:`argparge.Action` class that can check for correct extensions.

    Returns:
        argparse.Action: a class (not an instance) of an argparse action.
    """

    class Act(argparse.Action):
        def __call__(self, parser, namespace, fname, option_string=None):
            is_valid = any(map(lambda choice: fname[-len(choice):] == choice, choices))

            if not is_valid and dir_allowed and os.path.isdir(fname):
                is_valid = True

            if is_valid:
                setattr(namespace, self.dest, fname)
            else:
                option_string = '({})'.format(option_string) if option_string else ''
                parser.error("File doesn't end with one of {}{}".format(choices, option_string))

    return Act 

def pytest_addoption(parser):
    group = parser.getgroup("sqlalchemy")

    def make_option(name, **kw):
        callback_ = kw.pop("callback", None)
        if callback_:
            class CallableAction(argparse.Action):
                def __call__(self, parser, namespace,
                             values, option_string=None):
                    callback_(option_string, values, parser)
            kw["action"] = CallableAction

        group.addoption(name, **kw)

    plugin_base.setup_options(make_option)
    plugin_base.read_config() 

def pytest_addoption(parser):
    group = parser.getgroup("sqlalchemy")

    def make_option(name, **kw):
        callback_ = kw.pop("callback", None)
        if callback_:
            class CallableAction(argparse.Action):
                def __call__(self, parser, namespace,
                             values, option_string=None):
                    callback_(option_string, values, parser)
            kw["action"] = CallableAction

        group.addoption(name, **kw)

    plugin_base.setup_options(make_option)
    plugin_base.read_config() 

def get_constrained_float_action(
    min_val: Optional[float] = None, max_val: Optional[float] = None
) -> Type[argparse.Action]:
    class ConstrainedFloatAction(argparse.Action):
        """Custom action for ensuring floats arguments meet these."""

        def __call__(self, parser, namespace, values, option_string=None):  # type: ignore
            if min_val is not None and values < min_val:
                parser.error("{0} must be no smaller than {1}.".format(option_string, min_val))
            if max_val is not None and values > max_val:
                parser.error("{0} must be no greater than {1}.".format(option_string, max_val))

            setattr(namespace, self.dest, values)

    return ConstrainedFloatAction 

def test_user_defined_action(self):

        class Success(Exception):
            pass

        class Action(object):

            def __init__(self,
                         option_strings,
                         dest,
                         const,
                         default,
                         required=False):
                if dest == 'spam':
                    if const is Success:
                        if default is Success:
                            raise Success()

            def __call__(self, *args, **kwargs):
                pass

        parser = argparse.ArgumentParser()
        self.assertRaises(Success, parser.add_argument, '--spam',
                          action=Action, default=Success, const=Success)
        self.assertRaises(Success, parser.add_argument, 'spam',
                          action=Action, default=Success, const=Success)

# ================================
# Actions returned by add_argument
# ================================ 

def test_optional(self):
        option = argparse.Action(
            option_strings=['--foo', '-a', '-b'],
            dest='b',
            type='int',
            nargs='+',
            default=42,
            choices=[1, 2, 3],
            help='HELP',
            metavar='METAVAR')
        string = (
            "Action(option_strings=['--foo', '-a', '-b'], dest='b', "
            "nargs='+', const=None, default=42, type='int', "
            "choices=[1, 2, 3], help='HELP', metavar='METAVAR')")
        self.assertStringEqual(option, string) 

def test_argument(self):
        argument = argparse.Action(
            option_strings=[],
            dest='x',
            type=float,
            nargs='?',
            default=2.5,
            choices=[0.5, 1.5, 2.5],
            help='H HH H',
            metavar='MV MV MV')
        string = (
            "Action(option_strings=[], dest='x', nargs='?', "
            "const=None, default=2.5, type=%r, choices=[0.5, 1.5, 2.5], "
            "help='H HH H', metavar='MV MV MV')" % float)
        self.assertStringEqual(argument, string) 

def choices(self, val):
        # argparse.Action will always try to set this value upon
        # instantiation, but this value should be dynamically
        # generated from the command table keys. So make this a
        # NOOP if argparse.Action tries to set this value.
        pass 

def required_length(nmin,nmax):
    class RequiredLength(argparse.Action):
        def __call__(self, parser, args, values, option_string=None):
            if not nmin<=len(values)<=nmax:
                msg='argument "{f}" requires between {nmin} and {nmax} arguments'.format(
                    f=self.dest,nmin=nmin,nmax=nmax)
                raise argparse.ArgumentTypeError(msg)
            setattr(args, self.dest, values)
    return RequiredLength 

def test_user_defined_action(self):

        class Success(Exception):
            pass

        class Action(object):

            def __init__(self,
                         option_strings,
                         dest,
                         const,
                         default,
                         required=False):
                if dest == 'spam':
                    if const is Success:
                        if default is Success:
                            raise Success()

            def __call__(self, *args, **kwargs):
                pass

        parser = argparse.ArgumentParser()
        self.assertRaises(Success, parser.add_argument, '--spam',
                          action=Action, default=Success, const=Success)
        self.assertRaises(Success, parser.add_argument, 'spam',
                          action=Action, default=Success, const=Success)

# ================================
# Actions returned by add_argument
# ================================ 

def test_optional(self):
        option = argparse.Action(
            option_strings=['--foo', '-a', '-b'],
            dest='b',
            type='int',
            nargs='+',
            default=42,
            choices=[1, 2, 3],
            help='HELP',
            metavar='METAVAR')
        string = (
            "Action(option_strings=['--foo', '-a', '-b'], dest='b', "
            "nargs='+', const=None, default=42, type='int', "
            "choices=[1, 2, 3], help='HELP', metavar='METAVAR')")
        self.assertStringEqual(option, string) 

def test_argument(self):
        argument = argparse.Action(
            option_strings=[],
            dest='x',
            type=float,
            nargs='?',
            default=2.5,
            choices=[0.5, 1.5, 2.5],
            help='H HH H',
            metavar='MV MV MV')
        string = (
            "Action(option_strings=[], dest='x', nargs='?', "
            "const=None, default=2.5, type=%r, choices=[0.5, 1.5, 2.5], "
            "help='H HH H', metavar='MV MV MV')" % float)
        self.assertStringEqual(argument, string) 

def _get_parent_class(self, **kwargs):
        # wrap any existing action
        action = kwargs.get('action', None)
        parent_class = argparse.Action

        # action is either a user-defined Action class or a string referring a library-defined Action
        if isinstance(action, type) and issubclass(action, argparse.Action):
            parent_class = action
        elif isinstance(action, str):
            parent_class = self.command_loader.cli_ctx.invocation.parser._registries['action'][action]  # pylint: disable=protected-access
        return parent_class 

def setUp(self):
        from knack.help_files import helps

        class LoggerAction(argparse.Action):

            def __call__(self, parser, namespace, values, option_string=None):
                print("Side-effect from some original action!", file=sys.stderr)

        class PreviewTestCommandLoader(CLICommandsLoader):
            def load_command_table(self, args):
                super(PreviewTestCommandLoader, self).load_command_table(args)
                with CommandGroup(self, '', '{}#{{}}'.format(__name__)) as g:
                    g.command('arg-test', 'example_arg_handler')
                return self.command_table

            def load_arguments(self, command):
                with ArgumentsContext(self, 'arg-test') as c:
                    c.argument('arg1', help='Arg1', is_preview=True, action=LoggerAction)

                super(PreviewTestCommandLoader, self).load_arguments(command)

        helps['grp1'] = """
    type: group
    short-summary: A group.
"""
        self.cli_ctx = DummyCLI(commands_loader_cls=PreviewTestCommandLoader) 

def check(validator):
    class CustomAction(argparse.Action):
        def __call__(self, parser, namespace, values, option_string=None):
            validator(values)
            setattr(namespace, self.dest, values)

    return CustomAction 

def check_size(min_size=None, max_size=None):
    class CustomAction(argparse.Action):
        def __call__(self, parser, namespace, values, option_string=None):
            validate((values, self.type, min_size, max_size, self.dest))
            setattr(namespace, self.dest, values)

    return CustomAction 

def arg_deprecated_action(new_arg):  # pragma: no cover
    class ArgDeprecated(argparse.Action):
        def __call__(self, parser, namespace, values, option_string=None):
            logger.warning('Argument %s deprecated. Use %s instead',
                           '|'.join(self.option_strings), new_arg)
            setattr(namespace, self.dest, values)
    return ArgDeprecated 

def __init__(self, option_strings, dest, field, **kwargs):
        self.field = field
        logger.debug(f"Creating Custom Action for field {field}")
        super().__init__(option_strings, dest, **self.field.arg_options) 

def parse():
    def nargs_range(nmin, nmax):
        class NargsRange(argparse.Action):
            def __call__(self, parser, args, values, option_string=None):
                if not nmin <= len(values) <= nmax:
                    msg = '"{f}" requires between {nmin} and {nmax} arguments'.format(
                        f=self.dest, nmin=nmin, nmax=nmax)
                    raise argparse.ArgumentTypeError(msg)
                setattr(args, self.dest, values)
        return NargsRange

    parser = argparse.ArgumentParser()
    parser.add_argument('files', nargs='+',
                        help="Input FITS files")
    parser.add_argument('-o', '--order', type=int,
                        help="PV order")
    parser.add_argument('-r', '--radial', action='store_true',
                        help="Use the radial term")
    parser.add_argument('-n', '--ndata', type=int, default=[64, 64],
                        action=nargs_range(1, 2), nargs='+',
                        help="Use n x n pixels to solve")
    parser.add_argument('--ext', action='append',
                        help="Extension to correct; "
                        "option can be used multiple times. "
                        "Default is the primary hdu.")
    parser.add_argument('-v', '--verbose', action='count', default=0,
                        help="Verbose level")
    args = parser.parse_args()

    if len(args.ndata) == 1:
        args.ndata = [args.ndata[0], args.ndata[0]]
    if not args.ext:
        args.ext = [0]

    return args 

def parse_args():
    def nargs_range(nmin, nmax):
        class NargsRange(argparse.Action):
            def __call__(self, parser, args, values, option_string=None):
                if not nmin <= len(values) <= nmax:
                    msg = '"{f}" requires between {nmin} and {nmax} arguments'.format(
                        f=self.dest, nmin=nmin, nmax=nmax)
                    raise argparse.ArgumentTypeError(msg)
                setattr(args, self.dest, values)
        return NargsRange


    parser = argparse.ArgumentParser()
    parser.add_argument('files', nargs='+',
                        help="Input FITS files")
    parser.add_argument('-o', '--order', type=int,
                        help="PV order")
    parser.add_argument('-r', '--radial', action='store_true',
                        help="Use the radial term")
    parser.add_argument('-n', '--ndata', type=int, default=[64, 64],
                        action=nargs_range(1, 2), nargs='+',
                        help="Use n x n pixels to solve")
    parser.add_argument('--ext', action='append',
                        help="Extension to correct; "
                        "option can be used multiple times. "
                        "Default is the primary hdu.")
    parser.add_argument('-v', '--verbose', action='count', default=0,
                        help="Verbose level")
    args = parser.parse_args()

    if len(args.ndata) == 1:
        args.ndata = [args.ndata[0], args.ndata[0]]
    if not args.ext:
        args.ext = [0]

    return args 

def required_length(nmin,nmax):
    '''
    Raises error through argparse if length of optional
    arguments for an option is not within specified bounds.
    
    '''
    class RequiredLength(argparse.Action):
        def __call__(self, parser, args, values, option_string=None):
            if not nmin<=len(values)<=nmax:
                msg='argument "{f}" requires between {nmin} and {nmax} arguments'.format(f=self.dest,nmin=nmin,nmax=nmax)
                raise argparse.ArgumentTypeError(msg)
            setattr(args, self.dest, values)
    return RequiredLength 

def test_user_defined_action(self):

        class Success(Exception):
            pass

        class Action(object):

            def __init__(self,
                         option_strings,
                         dest,
                         const,
                         default,
                         required=False):
                if dest == 'spam':
                    if const is Success:
                        if default is Success:
                            raise Success()

            def __call__(self, *args, **kwargs):
                pass

        parser = argparse.ArgumentParser()
        self.assertRaises(Success, parser.add_argument, '--spam',
                          action=Action, default=Success, const=Success)
        self.assertRaises(Success, parser.add_argument, 'spam',
                          action=Action, default=Success, const=Success)

# ================================
# Actions returned by add_argument
# ================================ 

def test_optional(self):
        option = argparse.Action(
            option_strings=['--foo', '-a', '-b'],
            dest='b',
            type='int',
            nargs='+',
            default=42,
            choices=[1, 2, 3],
            help='HELP',
            metavar='METAVAR')
        string = (
            "Action(option_strings=['--foo', '-a', '-b'], dest='b', "
            "nargs='+', const=None, default=42, type='int', "
            "choices=[1, 2, 3], help='HELP', metavar='METAVAR')")
        self.assertStringEqual(option, string) 

def test_argument(self):
        argument = argparse.Action(
            option_strings=[],
            dest='x',
            type=float,
            nargs='?',
            default=2.5,
            choices=[0.5, 1.5, 2.5],
            help='H HH H',
            metavar='MV MV MV')
        string = (
            "Action(option_strings=[], dest='x', nargs='?', "
            "const=None, default=2.5, type=%r, choices=[0.5, 1.5, 2.5], "
            "help='H HH H', metavar='MV MV MV')" % float)
        self.assertStringEqual(argument, string) 

def pytest_addoption(parser):
    group = parser.getgroup("sqlalchemy")

    def make_option(name, **kw):
        callback_ = kw.pop("callback", None)
        if callback_:
            class CallableAction(argparse.Action):
                def __call__(self, parser, namespace,
                             values, option_string=None):
                    callback_(option_string, values, parser)
            kw["action"] = CallableAction

        zeroarg_callback = kw.pop("zeroarg_callback", None)
        if zeroarg_callback:
            class CallableAction(argparse.Action):
                def __init__(self, option_strings,
                             dest, default=False,
                             required=False, help=None):
                        super(CallableAction, self).__init__(
                            option_strings=option_strings,
                            dest=dest,
                            nargs=0,
                            const=True,
                            default=default,
                            required=required,
                            help=help)

                def __call__(self, parser, namespace,
                             values, option_string=None):
                    zeroarg_callback(option_string, values, parser)
            kw["action"] = CallableAction

        group.addoption(name, **kw)

    plugin_base.setup_options(make_option)
    plugin_base.read_config() 

def add_argument(self, parser):
        """If self.definition['options'] is set, add the appropriate argument
        to the parser.

        Args:
          parser (argparse.ArgumentParser): the parser to add the argument to.

        Returns:
          argparse.Action: on success.

        Raises:
          ScriptHarnessException: on argparse.ArgumentParser.add_argument
            error.
        """
        if not self.definition.get('options'):
            return

        args = self.definition['options']
        kwargs = {
            'dest': self.name,
            'action': self.definition.get('action', None),
        }
        for key in self.definition.keys():
            if key not in ('dest', 'action', 'options', 'validate_cb',
                           'incompatible_vars', 'required_vars',
                           'optional_vars', 'parent_parser'):
                kwargs[key] = self.definition[key]
        try:
            return parser.add_argument(*args, **kwargs)
        except ValueError as exc_info:
            raise ScriptHarnessException(
                "Error adding %s argument to parser!" % self.name,
                exc_info
            ) 

def test_user_defined_action(self):

        class Success(Exception):
            pass

        class Action(object):

            def __init__(self,
                         option_strings,
                         dest,
                         const,
                         default,
                         required=False):
                if dest == 'spam':
                    if const is Success:
                        if default is Success:
                            raise Success()

            def __call__(self, *args, **kwargs):
                pass

        parser = argparse.ArgumentParser()
        self.assertRaises(Success, parser.add_argument, '--spam',
                          action=Action, default=Success, const=Success)
        self.assertRaises(Success, parser.add_argument, 'spam',
                          action=Action, default=Success, const=Success)

# ================================
# Actions returned by add_argument
# ================================ 

def test_optional(self):
        option = argparse.Action(
            option_strings=['--foo', '-a', '-b'],
            dest='b',
            type='int',
            nargs='+',
            default=42,
            choices=[1, 2, 3],
            help='HELP',
            metavar='METAVAR')
        string = (
            "Action(option_strings=['--foo', '-a', '-b'], dest='b', "
            "nargs='+', const=None, default=42, type='int', "
            "choices=[1, 2, 3], help='HELP', metavar='METAVAR')")
        self.assertStringEqual(option, string) 

def test_argument(self):
        argument = argparse.Action(
            option_strings=[],
            dest='x',
            type=float,
            nargs='?',
            default=2.5,
            choices=[0.5, 1.5, 2.5],
            help='H HH H',
            metavar='MV MV MV')
        string = (
            "Action(option_strings=[], dest='x', nargs='?', "
            "const=None, default=2.5, type=%r, choices=[0.5, 1.5, 2.5], "
            "help='H HH H', metavar='MV MV MV')" % float)
        self.assertStringEqual(argument, string) 

def set_resnet_aug(aug):
    # standard data augmentation setting for resnet training
    aug.set_defaults(random_crop=0, random_resized_crop=1)
    aug.set_defaults(random_mirror=1)
    aug.set_defaults(min_random_area=0.08)
    aug.set_defaults(max_random_aspect_ratio=4./3., min_random_aspect_ratio=3./4.)
    aug.set_defaults(brightness=0.4, contrast=0.4, saturation=0.4, pca_noise=0.1)

# Action to translate --set-data-aug-level <N> arg to its component settings. 

def set_resnet_aug(aug):
    # standard data augmentation setting for resnet training
    aug.set_defaults(random_crop=0, random_resized_crop=1)
    aug.set_defaults(random_mirror=1)
    aug.set_defaults(min_random_area=0.08)
    aug.set_defaults(max_random_aspect_ratio=4./3., min_random_aspect_ratio=3./4.)
    aug.set_defaults(brightness=0.4, contrast=0.4, saturation=0.4, pca_noise=0.1)

# Action to translate --set-data-aug-level <N> arg to its component settings. 

def _resolve_choices_for_arg(self, action: argparse.Action, used_values=()) -> List[str]:
        if action.dest in self._arg_choices:
            args = self._arg_choices[action.dest]

            # is the argument a string? If so, see if we can find an attribute in the
            # application matching the string.
            if isinstance(args, str):
                try:
                    args = getattr(self._cmd2_app, args)
                except AttributeError:
                    # Couldn't find anything matching the name
                    return []

            # is the provided argument a callable. If so, call it
            if callable(args):
                try:
                    if self._cmd2_app is not None:
                        try:
                            args = args(self._cmd2_app)
                        except TypeError:
                            args = args()
                    else:
                        args = args()
                except TypeError:
                    return []

            try:
                iter(args)
            except TypeError:
                pass
            else:
                # filter out arguments we already used
                args = [arg for arg in args if arg not in used_values]

                if len(args) > 0:
                    return args

        return [] 

def obsoleted_by(new_dest):
    class ObsoletedByAction(argparse.Action):
        def __call__(self, parser, namespace, values, option_string=None):
            old_dest = option_string or self.dest
            print('%s is obsolete! See help for more details.' % old_dest)
            setattr(namespace, new_dest, values)
    return ObsoletedByAction