Fixed #4877 -- Fixed typo in testing documentation, patch from John Shaffer.

git-svn-id: http://code.djangoproject.com/svn/django/trunk@5702 bcc190cf-cafb-0310-a4f2-bffc1f526a37

docs/testing.txt

@@ -62,7 +62,7 @@ model-level doctests in the docstring for each model.
 
 For example::
 
-    from django.db import model
+    from django.db import models
 
     class Animal(models.Model):
         """