How to use the pynamodb.attributes.UTCDateTimeAttribute function in pynamodb

def test_utc_date_time_serialize(self):
        """
        UTCDateTimeAttribute.serialize
        """
        tstamp = datetime.now()
        attr = UTCDateTimeAttribute()
        assert attr.serialize(tstamp) == tstamp.replace(tzinfo=UTC).strftime(DATETIME_FORMAT)

host = "http://localhost:8000"
        projection = AllProjection()

    winner_id = UnicodeAttribute(hash_key=True)
    created_time = UnicodeAttribute(range_key=True)


class GameModel(Model):
    class Meta:
        read_capacity_units = 1
        write_capacity_units = 1
        table_name = "GameModel"
        host = "http://localhost:8000"

    player_id = UnicodeAttribute(hash_key=True)
    created_time = UTCDateTimeAttribute(range_key=True)
    winner_id = UnicodeAttribute()
    loser_id = UnicodeAttribute(null=True)

    player_opponent_index = GamePlayerOpponentIndex()
    opponent_time_index = GameOpponentTimeIndex()


class OldStyleModel(Model):
    _table_name = 'IndexedModel'
    user_name = UnicodeAttribute(hash_key=True)


class EmailIndex(GlobalSecondaryIndex):
    """
    A global secondary index for email addresses
    """

def test_utc_date_time_deserialize(self):
        """
        UTCDateTimeAttribute.deserialize
        """
        tstamp = datetime.now(UTC)
        attr = UTCDateTimeAttribute()
        assert attr.deserialize(tstamp.strftime(DATETIME_FORMAT)) == tstamp

@convert_pynamo_attribute.register(attributes.UTCDateTimeAttribute)
def convert_date_to_string(type, attribute, registry=None):
    return String(description=getattr(attribute, 'attr_name'),
                  required=not (getattr(attribute, 'null', True)))

index_name = "github-user-external-id-index"
        write_capacity_units = int(cla.conf["DYNAMO_WRITE_UNITS"])
        read_capacity_units = int(cla.conf["DYNAMO_READ_UNITS"])
        projection = AllProjection()

    user_external_id = UnicodeAttribute(hash_key=True)


class BaseModel(Model):
    """
    Base pynamodb model used for all CLA models.
    """

    date_created = UTCDateTimeAttribute(default=datetime.datetime.now())
    date_modified = UTCDateTimeAttribute(default=datetime.datetime.now())
    version = UnicodeAttribute(default="v1")  # Schema version.

    def __iter__(self):
        """Used to convert model to dict for JSON-serialized string."""
        for name, attr in self.get_attributes().items():
            if isinstance(attr, ListAttribute):
                if attr is None or getattr(self, name) is None:
                    yield name, None
                else:
                    values = attr.serialize(getattr(self, name))
                    if len(values) < 1:
                        yield name, []
                    else:
                        key = list(values[0].keys())[0]
                        yield name, [value[key] for value in values]
            else:

class Cajero(Model):
    class Meta:
        table_name = 'ubicajeros_cajeros'
        host = dynamodb_host

    address = UnicodeAttribute()
    id = UnicodeAttribute(hash_key=True)
    lat = NumberAttribute(null=True)
    lon = NumberAttribute(null=True)
    open_hours = UnicodeAttribute(null=True)
    org_code = NumberAttribute(null=True)
    org_name = UnicodeAttribute(null=True)
    state = UnicodeAttribute(null=True)
    updated_at = UTCDateTimeAttribute(default=datetime.utcnow())
    zip_code = UnicodeAttribute(null=True)

    def to_dict(self):
        return self.__dict__['attribute_values']

log.propagate = True


class Thread(Model):
    class Meta:
        read_capacity_units = 1
        write_capacity_units = 1
        table_name = "Thread"
        host = "http://localhost:8000"
    forum_name = UnicodeAttribute(hash_key=True)
    subject = UnicodeAttribute(range_key=True)
    views = NumberAttribute(default=0)
    replies = NumberAttribute(default=0)
    answered = NumberAttribute(default=0)
    tags = UnicodeSetAttribute()
    last_post_datetime = UTCDateTimeAttribute(null=True)

# Delete the table
# print(Thread.delete_table())

# Create the table
if not Thread.exists():
    Thread.create_table(wait=True)

# Create a thread
thread_item = Thread(
    'Some Forum',
    'Some Subject',
    tags=['foo', 'bar'],
    last_post_datetime=datetime.now()
)

class AssetModel(Model):
    class Meta:
        table_name = os.environ['DYNAMODB_TABLE']
        if 'ENV' in os.environ:
            host = 'http://localhost:8000'
        else:
            region = os.environ['REGION']
            host = os.environ['DYNAMODB_HOST']
            # 'https://dynamodb.us-east-1.amazonaws.com'

    asset_id = UnicodeAttribute(hash_key=True)
    state = UnicodeAttribute(null=False, default=State.CREATED.name)
    createdAt = UTCDateTimeAttribute(null=False, default=datetime.now().astimezone())
    updatedAt = UTCDateTimeAttribute(null=False, default=datetime.now().astimezone())

    def __str__(self):
        return 'asset_id:{}, state:{}'.format(self.asset_id, self.state)

    def get_key(self):
        return u'{}/{}'.format(KEY_BASE, self.asset_id)

    def save(self, conditional_operator=None, **expected_values):
        try:
            self.updatedAt = datetime.now().astimezone()
            logger.debug('saving: {}'.format(self))
            super(AssetModel, self).save()
        except Exception as e:
            logger.error('save {} failed: {}'.format(self.asset_id, e), exc_info=True)
            raise e

"""
    A DynamoDB Server Host.
    """

    class Meta:
        table_name = settings.value.DYNAMODB_TABLE_HOSTS
        if settings.value.APPLICATION_ENV == 'development':
            host = settings.value.DYNAMODB_URL
        session_cls = CustomPynamoSession

    service = UnicodeAttribute(hash_key=True)
    ip_address = UnicodeAttribute(range_key=True)
    service_repo_name_index = ServiceRepoNameIndex()
    service_repo_name = UnicodeAttribute(null=True)
    port = NumberAttribute()
    last_check_in = UTCDateTimeAttribute()
    revision = UnicodeAttribute()
    tags = JSONAttribute()

class ShoppingQuery(MapAttribute):
    # ref: https://developers.naver.com/docs/search/shopping/
    query = UnicodeAttribute()
    display = NumberAttribute(default=50)
    sort = UnicodeAttribute(default='sim')


class PriceRecord(Model):
    class Meta:
        table_name = "price_fairy_price_record"
        region = 'ap-northeast-2'

    product_id = UnicodeAttribute(hash_key=True)
    crawled_at = UTCDateTimeAttribute(range_key=True)

    item = MapAttribute()


class Product(Model):
    class Meta:
        table_name = "price_fairy_product"
        region = 'ap-northeast-2'

    id = UnicodeAttribute(hash_key=True)
    do_crawl = BooleanAttribute(default=False)
    created_at = UnicodeAttribute()
    last_crawled_at = UTCDateTimeAttribute(null=True)
    min_price = NumberAttribute(default=0)      # min_price 가격 이상인 결과만 사용

    queries = ListAttribute(of=ShoppingQuery)