How to use the pynamodb.settings.get_settings_value function in pynamodb

raise ValueError(
                        "The model has more than one Version attribute: {}, {}"
                        .format(cls._version_attribute_name, attr_name)
                    )
                cls._version_attribute_name = attr_name
        if isinstance(attrs, dict):
            for attr_name, attr_obj in attrs.items():
                if attr_name == META_CLASS_NAME:
                    if not hasattr(attr_obj, REGION):
                        setattr(attr_obj, REGION, get_settings_value('region'))
                    if not hasattr(attr_obj, HOST):
                        setattr(attr_obj, HOST, get_settings_value('host'))
                    if hasattr(attr_obj, 'session_cls') or hasattr(attr_obj, 'request_timeout_seconds'):
                        warnings.warn("The `session_cls` and `request_timeout_second` options are no longer supported")
                    if not hasattr(attr_obj, 'connect_timeout_seconds'):
                        setattr(attr_obj, 'connect_timeout_seconds', get_settings_value('connect_timeout_seconds'))
                    if not hasattr(attr_obj, 'read_timeout_seconds'):
                        setattr(attr_obj, 'read_timeout_seconds', get_settings_value('read_timeout_seconds'))
                    if not hasattr(attr_obj, 'base_backoff_ms'):
                        setattr(attr_obj, 'base_backoff_ms', get_settings_value('base_backoff_ms'))
                    if not hasattr(attr_obj, 'max_retry_attempts'):
                        setattr(attr_obj, 'max_retry_attempts', get_settings_value('max_retry_attempts'))
                    if not hasattr(attr_obj, 'max_pool_connections'):
                        setattr(attr_obj, 'max_pool_connections', get_settings_value('max_pool_connections'))
                    if not hasattr(attr_obj, 'extra_headers'):
                        setattr(attr_obj, 'extra_headers', get_settings_value('extra_headers'))
                    if not hasattr(attr_obj, 'aws_access_key_id'):
                        setattr(attr_obj, 'aws_access_key_id', None)
                    if not hasattr(attr_obj, 'aws_secret_access_key'):
                        setattr(attr_obj, 'aws_secret_access_key', None)
                    if not hasattr(attr_obj, 'aws_session_token'):
                        setattr(attr_obj, 'aws_session_token', None)

if not hasattr(attr_obj, HOST):
                        setattr(attr_obj, HOST, get_settings_value('host'))
                    if hasattr(attr_obj, 'session_cls') or hasattr(attr_obj, 'request_timeout_seconds'):
                        warnings.warn("The `session_cls` and `request_timeout_second` options are no longer supported")
                    if not hasattr(attr_obj, 'connect_timeout_seconds'):
                        setattr(attr_obj, 'connect_timeout_seconds', get_settings_value('connect_timeout_seconds'))
                    if not hasattr(attr_obj, 'read_timeout_seconds'):
                        setattr(attr_obj, 'read_timeout_seconds', get_settings_value('read_timeout_seconds'))
                    if not hasattr(attr_obj, 'base_backoff_ms'):
                        setattr(attr_obj, 'base_backoff_ms', get_settings_value('base_backoff_ms'))
                    if not hasattr(attr_obj, 'max_retry_attempts'):
                        setattr(attr_obj, 'max_retry_attempts', get_settings_value('max_retry_attempts'))
                    if not hasattr(attr_obj, 'max_pool_connections'):
                        setattr(attr_obj, 'max_pool_connections', get_settings_value('max_pool_connections'))
                    if not hasattr(attr_obj, 'extra_headers'):
                        setattr(attr_obj, 'extra_headers', get_settings_value('extra_headers'))
                    if not hasattr(attr_obj, 'aws_access_key_id'):
                        setattr(attr_obj, 'aws_access_key_id', None)
                    if not hasattr(attr_obj, 'aws_secret_access_key'):
                        setattr(attr_obj, 'aws_secret_access_key', None)
                    if not hasattr(attr_obj, 'aws_session_token'):
                        setattr(attr_obj, 'aws_session_token', None)
                elif isinstance(attr_obj, Index):
                    attr_obj.Meta.model = cls
                    if not hasattr(attr_obj.Meta, "index_name"):
                        attr_obj.Meta.index_name = attr_name
                elif isinstance(attr_obj, Attribute):
                    if attr_obj.attr_name is None:
                        attr_obj.attr_name = attr_name

            ttl_attr_names = [name for name, attr_obj in attrs.items() if isinstance(attr_obj, TTLAttribute)]
            if len(ttl_attr_names) > 1:

def __init__(self, region=None, host=None,
                 read_timeout_seconds=None, connect_timeout_seconds=None,
                 max_retry_attempts=None, base_backoff_ms=None,
                 max_pool_connections=None, extra_headers=None):
        self._tables = {}
        self.host = host
        self._local = local()
        self._client = None
        if region:
            self.region = region
        else:
            self.region = get_settings_value('region')

        if connect_timeout_seconds is not None:
            self._connect_timeout_seconds = connect_timeout_seconds
        else:
            self._connect_timeout_seconds = get_settings_value('connect_timeout_seconds')

        if read_timeout_seconds is not None:
            self._read_timeout_seconds = read_timeout_seconds
        else:
            self._read_timeout_seconds = get_settings_value('read_timeout_seconds')

        if max_retry_attempts is not None:
            self._max_retry_attempts_exception = max_retry_attempts
        else:
            self._max_retry_attempts_exception = get_settings_value('max_retry_attempts')

if not hasattr(attr_obj, REGION):
                        setattr(attr_obj, REGION, get_settings_value('region'))
                    if not hasattr(attr_obj, HOST):
                        setattr(attr_obj, HOST, get_settings_value('host'))
                    if hasattr(attr_obj, 'session_cls') or hasattr(attr_obj, 'request_timeout_seconds'):
                        warnings.warn("The `session_cls` and `request_timeout_second` options are no longer supported")
                    if not hasattr(attr_obj, 'connect_timeout_seconds'):
                        setattr(attr_obj, 'connect_timeout_seconds', get_settings_value('connect_timeout_seconds'))
                    if not hasattr(attr_obj, 'read_timeout_seconds'):
                        setattr(attr_obj, 'read_timeout_seconds', get_settings_value('read_timeout_seconds'))
                    if not hasattr(attr_obj, 'base_backoff_ms'):
                        setattr(attr_obj, 'base_backoff_ms', get_settings_value('base_backoff_ms'))
                    if not hasattr(attr_obj, 'max_retry_attempts'):
                        setattr(attr_obj, 'max_retry_attempts', get_settings_value('max_retry_attempts'))
                    if not hasattr(attr_obj, 'max_pool_connections'):
                        setattr(attr_obj, 'max_pool_connections', get_settings_value('max_pool_connections'))
                    if not hasattr(attr_obj, 'extra_headers'):
                        setattr(attr_obj, 'extra_headers', get_settings_value('extra_headers'))
                    if not hasattr(attr_obj, 'aws_access_key_id'):
                        setattr(attr_obj, 'aws_access_key_id', None)
                    if not hasattr(attr_obj, 'aws_secret_access_key'):
                        setattr(attr_obj, 'aws_secret_access_key', None)
                    if not hasattr(attr_obj, 'aws_session_token'):
                        setattr(attr_obj, 'aws_session_token', None)
                elif isinstance(attr_obj, Index):
                    attr_obj.Meta.model = cls
                    if not hasattr(attr_obj.Meta, "index_name"):
                        attr_obj.Meta.index_name = attr_name
                elif isinstance(attr_obj, Attribute):
                    if attr_obj.attr_name is None:
                        attr_obj.attr_name = attr_name

for attr_name, attr_obj in attrs.items():
                if attr_name == META_CLASS_NAME:
                    if not hasattr(attr_obj, REGION):
                        setattr(attr_obj, REGION, get_settings_value('region'))
                    if not hasattr(attr_obj, HOST):
                        setattr(attr_obj, HOST, get_settings_value('host'))
                    if hasattr(attr_obj, 'session_cls') or hasattr(attr_obj, 'request_timeout_seconds'):
                        warnings.warn("The `session_cls` and `request_timeout_second` options are no longer supported")
                    if not hasattr(attr_obj, 'connect_timeout_seconds'):
                        setattr(attr_obj, 'connect_timeout_seconds', get_settings_value('connect_timeout_seconds'))
                    if not hasattr(attr_obj, 'read_timeout_seconds'):
                        setattr(attr_obj, 'read_timeout_seconds', get_settings_value('read_timeout_seconds'))
                    if not hasattr(attr_obj, 'base_backoff_ms'):
                        setattr(attr_obj, 'base_backoff_ms', get_settings_value('base_backoff_ms'))
                    if not hasattr(attr_obj, 'max_retry_attempts'):
                        setattr(attr_obj, 'max_retry_attempts', get_settings_value('max_retry_attempts'))
                    if not hasattr(attr_obj, 'max_pool_connections'):
                        setattr(attr_obj, 'max_pool_connections', get_settings_value('max_pool_connections'))
                    if not hasattr(attr_obj, 'extra_headers'):
                        setattr(attr_obj, 'extra_headers', get_settings_value('extra_headers'))
                    if not hasattr(attr_obj, 'aws_access_key_id'):
                        setattr(attr_obj, 'aws_access_key_id', None)
                    if not hasattr(attr_obj, 'aws_secret_access_key'):
                        setattr(attr_obj, 'aws_secret_access_key', None)
                    if not hasattr(attr_obj, 'aws_session_token'):
                        setattr(attr_obj, 'aws_session_token', None)
                elif isinstance(attr_obj, Index):
                    attr_obj.Meta.model = cls
                    if not hasattr(attr_obj.Meta, "index_name"):
                        attr_obj.Meta.index_name = attr_name
                elif isinstance(attr_obj, Attribute):
                    if attr_obj.attr_name is None:

self._connect_timeout_seconds = get_settings_value('connect_timeout_seconds')

        if read_timeout_seconds is not None:
            self._read_timeout_seconds = read_timeout_seconds
        else:
            self._read_timeout_seconds = get_settings_value('read_timeout_seconds')

        if max_retry_attempts is not None:
            self._max_retry_attempts_exception = max_retry_attempts
        else:
            self._max_retry_attempts_exception = get_settings_value('max_retry_attempts')

        if base_backoff_ms is not None:
            self._base_backoff_ms = base_backoff_ms
        else:
            self._base_backoff_ms = get_settings_value('base_backoff_ms')

        if max_pool_connections is not None:
            self._max_pool_connections = max_pool_connections
        else:
            self._max_pool_connections = get_settings_value('max_pool_connections')

        if extra_headers is not None:
            self._extra_headers = extra_headers
        else:
            self._extra_headers = get_settings_value('extra_headers')

if attribute.is_range_key:
                cls._range_keyname = attr_name
            if isinstance(attribute, VersionAttribute):
                if cls._version_attribute_name:
                    raise ValueError(
                        "The model has more than one Version attribute: {}, {}"
                        .format(cls._version_attribute_name, attr_name)
                    )
                cls._version_attribute_name = attr_name
        if isinstance(attrs, dict):
            for attr_name, attr_obj in attrs.items():
                if attr_name == META_CLASS_NAME:
                    if not hasattr(attr_obj, REGION):
                        setattr(attr_obj, REGION, get_settings_value('region'))
                    if not hasattr(attr_obj, HOST):
                        setattr(attr_obj, HOST, get_settings_value('host'))
                    if hasattr(attr_obj, 'session_cls') or hasattr(attr_obj, 'request_timeout_seconds'):
                        warnings.warn("The `session_cls` and `request_timeout_second` options are no longer supported")
                    if not hasattr(attr_obj, 'connect_timeout_seconds'):
                        setattr(attr_obj, 'connect_timeout_seconds', get_settings_value('connect_timeout_seconds'))
                    if not hasattr(attr_obj, 'read_timeout_seconds'):
                        setattr(attr_obj, 'read_timeout_seconds', get_settings_value('read_timeout_seconds'))
                    if not hasattr(attr_obj, 'base_backoff_ms'):
                        setattr(attr_obj, 'base_backoff_ms', get_settings_value('base_backoff_ms'))
                    if not hasattr(attr_obj, 'max_retry_attempts'):
                        setattr(attr_obj, 'max_retry_attempts', get_settings_value('max_retry_attempts'))
                    if not hasattr(attr_obj, 'max_pool_connections'):
                        setattr(attr_obj, 'max_pool_connections', get_settings_value('max_pool_connections'))
                    if not hasattr(attr_obj, 'extra_headers'):
                        setattr(attr_obj, 'extra_headers', get_settings_value('extra_headers'))
                    if not hasattr(attr_obj, 'aws_access_key_id'):
                        setattr(attr_obj, 'aws_access_key_id', None)

if attribute.is_hash_key:
                cls._hash_keyname = attr_name
            if attribute.is_range_key:
                cls._range_keyname = attr_name
            if isinstance(attribute, VersionAttribute):
                if cls._version_attribute_name:
                    raise ValueError(
                        "The model has more than one Version attribute: {}, {}"
                        .format(cls._version_attribute_name, attr_name)
                    )
                cls._version_attribute_name = attr_name
        if isinstance(attrs, dict):
            for attr_name, attr_obj in attrs.items():
                if attr_name == META_CLASS_NAME:
                    if not hasattr(attr_obj, REGION):
                        setattr(attr_obj, REGION, get_settings_value('region'))
                    if not hasattr(attr_obj, HOST):
                        setattr(attr_obj, HOST, get_settings_value('host'))
                    if hasattr(attr_obj, 'session_cls') or hasattr(attr_obj, 'request_timeout_seconds'):
                        warnings.warn("The `session_cls` and `request_timeout_second` options are no longer supported")
                    if not hasattr(attr_obj, 'connect_timeout_seconds'):
                        setattr(attr_obj, 'connect_timeout_seconds', get_settings_value('connect_timeout_seconds'))
                    if not hasattr(attr_obj, 'read_timeout_seconds'):
                        setattr(attr_obj, 'read_timeout_seconds', get_settings_value('read_timeout_seconds'))
                    if not hasattr(attr_obj, 'base_backoff_ms'):
                        setattr(attr_obj, 'base_backoff_ms', get_settings_value('base_backoff_ms'))
                    if not hasattr(attr_obj, 'max_retry_attempts'):
                        setattr(attr_obj, 'max_retry_attempts', get_settings_value('max_retry_attempts'))
                    if not hasattr(attr_obj, 'max_pool_connections'):
                        setattr(attr_obj, 'max_pool_connections', get_settings_value('max_pool_connections'))
                    if not hasattr(attr_obj, 'extra_headers'):
                        setattr(attr_obj, 'extra_headers', get_settings_value('extra_headers'))

self.region = get_settings_value('region')

        if connect_timeout_seconds is not None:
            self._connect_timeout_seconds = connect_timeout_seconds
        else:
            self._connect_timeout_seconds = get_settings_value('connect_timeout_seconds')

        if read_timeout_seconds is not None:
            self._read_timeout_seconds = read_timeout_seconds
        else:
            self._read_timeout_seconds = get_settings_value('read_timeout_seconds')

        if max_retry_attempts is not None:
            self._max_retry_attempts_exception = max_retry_attempts
        else:
            self._max_retry_attempts_exception = get_settings_value('max_retry_attempts')

        if base_backoff_ms is not None:
            self._base_backoff_ms = base_backoff_ms
        else:
            self._base_backoff_ms = get_settings_value('base_backoff_ms')

        if max_pool_connections is not None:
            self._max_pool_connections = max_pool_connections
        else:
            self._max_pool_connections = get_settings_value('max_pool_connections')

        if extra_headers is not None:
            self._extra_headers = extra_headers
        else:
            self._extra_headers = get_settings_value('extra_headers')

.format(cls._version_attribute_name, attr_name)
                    )
                cls._version_attribute_name = attr_name
        if isinstance(attrs, dict):
            for attr_name, attr_obj in attrs.items():
                if attr_name == META_CLASS_NAME:
                    if not hasattr(attr_obj, REGION):
                        setattr(attr_obj, REGION, get_settings_value('region'))
                    if not hasattr(attr_obj, HOST):
                        setattr(attr_obj, HOST, get_settings_value('host'))
                    if hasattr(attr_obj, 'session_cls') or hasattr(attr_obj, 'request_timeout_seconds'):
                        warnings.warn("The `session_cls` and `request_timeout_second` options are no longer supported")
                    if not hasattr(attr_obj, 'connect_timeout_seconds'):
                        setattr(attr_obj, 'connect_timeout_seconds', get_settings_value('connect_timeout_seconds'))
                    if not hasattr(attr_obj, 'read_timeout_seconds'):
                        setattr(attr_obj, 'read_timeout_seconds', get_settings_value('read_timeout_seconds'))
                    if not hasattr(attr_obj, 'base_backoff_ms'):
                        setattr(attr_obj, 'base_backoff_ms', get_settings_value('base_backoff_ms'))
                    if not hasattr(attr_obj, 'max_retry_attempts'):
                        setattr(attr_obj, 'max_retry_attempts', get_settings_value('max_retry_attempts'))
                    if not hasattr(attr_obj, 'max_pool_connections'):
                        setattr(attr_obj, 'max_pool_connections', get_settings_value('max_pool_connections'))
                    if not hasattr(attr_obj, 'extra_headers'):
                        setattr(attr_obj, 'extra_headers', get_settings_value('extra_headers'))
                    if not hasattr(attr_obj, 'aws_access_key_id'):
                        setattr(attr_obj, 'aws_access_key_id', None)
                    if not hasattr(attr_obj, 'aws_secret_access_key'):
                        setattr(attr_obj, 'aws_secret_access_key', None)
                    if not hasattr(attr_obj, 'aws_session_token'):
                        setattr(attr_obj, 'aws_session_token', None)
                elif isinstance(attr_obj, Index):
                    attr_obj.Meta.model = cls