update some examples

examples/blogpost/resources.py

+from django.core.urlresolvers import reverse
+from djangorestframework.resources import ModelResource
+from blogpost.models import BlogPost, Comment
+
+
+class BlogPostResource(ModelResource):
+    """
+    A Blog Post has a *title* and *content*, and can be associated with zero or more comments.
+    """
+    model = BlogPost
+    fields = ('created', 'title', 'slug', 'content', 'url', 'comments')
+    ordering = ('-created',)
+
+    def comments(self, instance):
+        return reverse('comments', kwargs={'blogpost': instance.key}) 
+
+
+class CommentResource(ModelResource):
+    """
+    A Comment is associated with a given Blog Post and has a *username* and *comment*, and optionally a *rating*. 
+    """
+    model = Comment
+    fields = ('username', 'comment', 'created', 'rating', 'url', 'blogpost')
+    ordering = ('-created',)
+    
+    def blogpost(self, instance):
+        return reverse('blog-post', kwargs={'key': instance.blogpost.key}) 
\ No newline at end of file

examples/modelresourceexample/resources.py

+from djangorestframework.resources import ModelResource
+from modelresourceexample.models import MyModel
+
+class MyModelResource(ModelResource):
+    model = MyModel
+    fields = ('foo', 'bar', 'baz', 'url')
+    ordering = ('created',)