Made the database cache backend, which bypasses the ORM, compatible with time zone support.

git-svn-id: http://code.djangoproject.com/svn/django/trunk@17119 bcc190cf-cafb-0310-a4f2-bffc1f526a37

tests/regressiontests/cache/models.py

@@ -1,11 +1,11 @@
-from datetime import datetime
+from django.utils import timezone
 
 from django.db import models
 
 
 def expensive_calculation():
     expensive_calculation.num_runs += 1
-    return datetime.now()
+    return timezone.now()
 
 class Poll(models.Model):
     question = models.CharField(max_length=200)