Move urls.py changes down and add necessary import

The previous location of editting urls.py did not allow migrations to be created and the default import needs to be modified

Author: pbaehr

docs/tutorial/1-serialization.md

@@ -48,12 +48,6 @@ We'll need to add our new `snippets` app and the `rest_framework` app to `INSTAL
         'snippets',
     )
 
-We also need to wire up the root urlconf, in the `tutorial/urls.py` file, to include our snippet app's URLs.
-
-    urlpatterns = [
-        url(r'^', include('snippets.urls')),
-    ]
-
 Okay, we're ready to roll.
 
 ## Creating a model to work with
@@ -299,6 +293,14 @@ Finally we need to wire these views up.  Create the `snippets/urls.py` file:
         url(r'^snippets/$', views.snippet_list),
         url(r'^snippets/(?P<pk>[0-9]+)/$', views.snippet_detail),
     ]
+    
+We also need to wire up the root urlconf, in the `tutorial/urls.py` file, to include our snippet app's URLs.
+    
+    from django.conf.urls import url, include
+    
+    urlpatterns = [
+        url(r'^', include('snippets.urls')),
+    ]
 
 It's worth noting that there are a couple of edge cases we're not dealing with properly at the moment.  If we send malformed `json`, or if a request is made with a method that the view doesn't handle, then we'll end up with a 500 "server error" response.  Still, this'll do for now.