Python marshmallow.fields 模块，Date() 实例源码

def _deserialize(self, value, attr, data):
        if isinstance(value, datetime):
            return value
        return super()._deserialize(value, attr, data)


# class TimeField(BaseField, ma_fields.Time):
#     pass


# class DateField(BaseField, ma_fields.Date):
#     pass


# class TimeDeltaField(BaseField, ma_fields.TimeDelta):
#     pass