Python 如何在UserSerializer中添加显式字段

下面的错误是在django中的Python 3的新版本中显示的，我可以找出如何让URL运行.

from django.contrib import admin
from django.urls import path, include
from api.views import CreateUserView
from rest_framework_simplejwt.views import TokenObtainPairView, TokenRefreshView

urlpatterns = [
    path('admin/', admin.site.urls),
    path("api/user/register/", CreateUserView.as_view(), name="register"),
    path("api/token/", TokenObtainPairView.as_view(), name="get_token"),
    path("api/token/refresh", TokenRefreshView.as_view(), name="refresh"),
    path("api-auth/", include("rest_framework.urls")),
]

urls.py

from django.shortcuts import render
from django.contrib.auth.models import User
from rest_framework import generics
from .serializers import UserSerializer
from rest_framework.permissions import IsAuthenticated, AllowAny

# Create your views here.


class CreateUserView(generics.CreateAPIView):
    queryset = User.objects.all()
    serializer_class = UserSerializer
    permission_classes = [AllowAny]

views.py

 from django.contrib.auth.models import User
from rest_framework import serializers


class UserSerializer(serializers.ModelSerializer):
    class Meta:
        model = User
        field = ["id", "username", "password"]
        extra_kwargs = {"password": {"write_only": True}}

    def create(self, validated_data):
        user = User.objects.create_user(**validated_data)
        return user

serializers.py