android - Adding a custom DateTimeField that can be updated through a PUT request (DjangoRestFramework) -

i'm new django , created django app following tutorial: http://www.django-rest-framework.org/tutorial/quickstart/

this tutorial gives pre-made user class includes various fields. trying add custom datetimefield can updated through put request in android. how add custom field "timestamp" class.

here code:

serializers.py

from django.contrib.auth.models import user rest_framework import serializers django.contrib.auth.models import models  class userserializer(serializers.hyperlinkedmodelserializer):     class meta:         model = user         lookup_field = 'username'         set_timezone = 'date_joined'         fields = ('url', 'username','date_joined') 

views.py

from django.contrib.auth.models import user rest_framework import viewsets tutorial.quickstart.serializers import userserializer django.conf import settings django.shortcuts import redirect, render dir(settings) settings.__dict__    class userviewset(viewsets.modelviewset):     """     api endpoint allows users viewed or edited.     """     lookup_field = 'username'     queryset = user.objects.all()     serializer_class = userserializer 

urls.py

from django.conf.urls import url, include rest_framework import routers tutorial.quickstart import views  router = routers.defaultrouter() router.register(r'users', views.userviewset)  urlpatterns = [     url(r'^', include(router.urls)),     url(r'^api-auth/', include('rest_framework.urls', namespace='rest_framework')) ] 

models.py

from django.db import models # create models here. datetime import datetime  class time(models.model):    timestamp = models.datetimefield(auto_now_add=true)     def __unicode__(self):        return "time" 

error

exception value:
field name timestamp not valid model user. exception location: /library/python/2.7/site-packages/rest_framework/serializers.py in build_unknown_field, line 1079 python executable: /library/frameworks/python.framework/versions/2.7/resources/python.app/contents/macos/python python version: 2.7.6

you should better use abstractbaseuser django in order construct own user model. more simple creating new dedicated time model, , drf custom relational field goes it.

for example:

from django.contrib.auth.models import abstractbaseuser django.db import models  class customuser(abstractbaseuser):     timestamp = models.datetimefield() 

then, in drf serializer:

from rest_framework import serializers  class customuserserializer(serializers.hyperlinkedmodelserializer):     class meta:         model = customuser         lookup_field = 'username'         set_timezone = 'date_joined'         fields = ('url', 'username','date_joined', 'timestamp')