title: Django-Rest nested serialization OneToOne
body: <p>I've been looking and following the Django-Rest Official docs <a href="http://www.django-rest-framework.org/api-guide/relations/" rel="nofollow">here</a> and tried to base my approach on that, except I was using a OneToOne relationship.</p>
  
  <p>However, when I go to add in the browsable interface, it doesn't pick up the value in the nested text fields, and tells me that it can't be null. I've tried Googling and searching on here, but can't really find anything that works for getting a OneToOne relationship to work like what I want. I'm new to the REST-framework, and am just really confused. Thanks!</p>
  
  <p>Basically, each verb needs to have one past tense object, which has those three fields (for testing, more, or even another layer of nesting, will be added later). I just can't get them to add with the browsable API. </p>
  
  <p>Models.py:</p>
  
  <pre><code>from django.db import models
  
  class Verb(models.Model):
      verb = models.TextField()
      verbal_noun = models.TextField()
      verbal_adjective = models.TextField()
      present = models.TextField()
      future = models.TextField()
      habitual_present = models.TextField()
      conditional = models.TextField()
      past_habitual = models.TextField()
      past_subjunctive = models.TextField()
      present_subjunctive = models.TextField()
      imperative = models.TextField()
  
  class Past(models.Model):
      verb = models.OneToOneField(Verb)
      first_singular = models.TextField()
      second_singular = models.TextField()
      third_singular = models.TextField()
  </code></pre>
  
  <p>Serializers.py:</p>
  
  <pre><code>from rest_framework import serializers
  from conjugations.models import Verb, Past
  
  class PastSerializer(serializers.ModelSerializer):
      class Meta:
          model = Past
          fields = ('first_singular','second_singular','third_singular')
  
  class VerbSerializer(serializers.ModelSerializer):
      past = PastSerializer()
  
      class Meta:
          model = Verb
          fields = ('verb','verbal_noun','verbal_adjective','past','present',
                  'future','habitual_present','conditional','past_habitual',
                  'past_subjunctive','present_subjunctive','imperative' )
  
      def create(self, validated_data):
          past_data = validated_data.pop('past')
          verb = Verb.objects.create(**validated_data)
          for past in past_data:
              Past.objects.create(verb=verb, **past)
          return verb
  </code></pre>
  
  <p>Raw data input: </p>
  
  <pre><code>{
      "verb": "test",
      "verbal_noun": "test",
      "verbal_adjective": "test",
      "past": {
          "first_singular": "test1",
          "second_singular": "test2",
          "third_singular": "test3"
      },
      "present": "test",
      "future": "test",
      "habitual_present": "test",
      "conditional": "test",
      "past_habitual": "test",
      "past_subjunctive": "test",
      "present_subjunctive": "test",
      "imperative": "test"
  }
  </code></pre>
  
  <p>Views.py</p>
  
  <pre><code>from conjugations.models import Verb
  from conjugations.serializers import VerbSerializer
  from rest_framework import generics, permissions
  
  class VerbList(generics.ListCreateAPIView):
      queryset = Verb.objects.all()
      serializer_class = VerbSerializer
      permission_classes = (permissions.IsAuthenticatedOrReadOnly,)
  
  class VerbDetail(generics.RetrieveUpdateDestroyAPIView):
      queryset = Verb.objects.all()
      serializer_class = VerbSerializer
      permission_classes = (permissions.IsAuthenticatedOrReadOnly,)
  </code></pre>
  
  <p>Urls.py</p>
  
  <pre><code>from django.conf.urls import url
  from rest_framework.urlpatterns import format_suffix_patterns
  from conjugations import views
  
  urlpatterns = [
      url(r'^verbs/$', views.VerbList.as_view()),
      url(r'^verbs/(?P&lt;pk&gt;[0-9]+)/$', views.VerbDetail.as_view()),
  ]
  
  urlpatterns = format_suffix_patterns(urlpatterns)
  </code></pre>
  
  <p>Error:</p>
  
  <pre><code>File "/home/Projects/Python/virtualenvs/remnigh/lib/python3.5/site-packages/rest_framework/mixins.py", line 26, in perform_create
      serializer.save()
    File "/home/Projects/Python/virtualenvs/remnigh/lib/python3.5/site-packages/rest_framework/serializers.py", line 191, in save
      self.instance = self.create(validated_data)
    File "/home/Projects/Python/reimnigh-test/reimnigh/conjugations/serializers.py", line 19, in create
      past_data = validated_data.pop('past')
  KeyError: 'past'
  </code></pre>