title: Django: ModelViewSet router not working for update action
body: <p>I am using ModelViewSet and Modelserializer for a blog like project.</p>
  
  <p>It could be my difficulty in understanding the implementation; I can't get the <strong>update</strong> action to work via <strong>calling it through router</strong>, only the <em>list action is working</em> with the route I have defined.</p>
  
  <p>When I put the url : <code>127.0.0.1:8000/api/blogs/1</code>, to return the blog with ID 1 <strong>to edit</strong>, it returns <code>{"Detail": "Not Found."}</code>.</p>
  
  <p>This is my view:</p>
  
  <pre><code>class ArticleViewSet(viewsets.ModelViewSet):
      queryset = Article.objects.all()
      serializer_class = ArticleSerializer
  </code></pre>
  
  <p>I have also overridden the save and update methods in the serializer class, don't know whether it was needed for ModelViewSet in ModelSerializer.</p>
  
  <pre><code>class ArticleSerializer(serializers.ModelSerializer):
  
      def create(self, validated_data):
          article = Article.objects.create(
              article_title = self.validated_data['article_title'],
              article_content = self.validated_data['article_content'],
              ...
          )
          return article
  
      def update(self, instance, validated_data):
          instance.article_title = validated_data.get('article_title', instance.article_title)
          instance.article_content = validated_data.get('article_content', instance.article_content)
          ...
          instance.save()
          return instance
  
      class Meta:
          model = Article
          fields = ...
  </code></pre>
  
  <p>And the <code>urls.py</code> file:</p>
  
  <pre><code>router = DefaultRouter()
  router.register(r'blogs', ArticleViewSet, basename='articles-list')
  urlpatterns = router.urls
  </code></pre>
  
  <p>My question is:
  1. How do I specify urls for the ModelViewSet actions (in my case the <code>update</code> action)?
  2. Will defining only one url suffice all my needs with <strong>every</strong> ModelViewSet actions? if so how?</p>
  
  <p>What am I doing wrong? I'm new to DRF.</p>