properties.py 文件源码

def _serialize(cls, value):
        if isinstance(value, model.Model):
            kind, value = cls.Extensions.Model, cls._entity_to_dict(value)

        elif isinstance(value, datetime):
            kind, value = cls.Extensions.DateTime, _seconds_since_epoch(value)

        else:
            raise TypeError(f"Value of type {type(value)} cannot be serialized.")

        return msgpack.ExtType(kind, cls._dumps(value))