pyorient+Django:我应该如何正确地创建一个模型,以便序列化程序能够访问它们?

设置.py

from pyorient.ogm import declarative
Node = declarative.declarative_node()
Relationship = declarative.declarative_relationship()

型号/用户.py

from pyorient.ogm.property import *
from my_proj.settings import Node


class User(Node):
    email = String(unique=True)
    password = String()

序列化程序/register_serializer.py

from rest_framework import serializers, validators
from users.models.user import User


class RegisterSerializer(serializers.ModelSerializer):
    class Meta:
        model = User
        fields = ('email', 'password')

我得到以下异常

AttributeError: type object 'User' has no attribute '_meta