"date": datetime(2021, 7, 26).isoformat(),
            "price": None,
            "owner_ids": None,
        },
        {
            "name": "bar",
            "date": datetime(2021, 7, 26).isoformat(),
            "price": 1.0,
            "owner_ids": None,
        },
        {
            "name": "baz",
            "date": datetime(2021, 7, 26).isoformat(),
            "price": 2.0,

    instance = MyModel(dt_field=safe_datetime.now())

    encoded_instance = jsonable_encoder(
        instance, custom_encoder={safe_datetime: lambda o: o.isoformat()}
    )
    assert encoded_instance["dt_field"] == instance.dt_field.isoformat()


def test_custom_enum_encoders():
    def custom_enum_encoder(v: Enum):
        return v.value.lower()

    class MyEnum(Enum):

        dt_field: datetime

        @field_serializer("dt_field")
        def serialize_datetime(self, dt_field: datetime):
            return dt_field.replace(microsecond=0, tzinfo=timezone.utc).isoformat()

    app = FastAPI()
    model = ModelWithDatetimeField(dt_field=datetime(2019, 1, 1, 8))

    @app.get("/model", response_model=ModelWithDatetimeField)
    def get_model():
        return model

                secret_key=creds.get_child_text('SecretAccessKey'),
                token=creds.get_child_text('SessionToken'),
                expiry_time=parse(creds.get_child_text('Expiration')).isoformat())