cached property

content/models.py

@@ -8,6 +8,7 @@ from django.utils.html import mark_safe
 from django.utils.encoding import python_2_unicode_compatible
 from django.db.models.signals import m2m_changed
 from django.dispatch import receiver
+from django.utils.functional import cached_property
 
 
 from photologue.models import Photo, Gallery
@@ -155,7 +156,7 @@ class Content(models.Model):
         if src:
             return mark_safe(u'<a href="{}"><img src="{}"></a>'.format(self.get_absolute_url(), src))
 
-    @property
+    @cached_property
     def image_url(self):
         if self.photo:
             url = self.photo.image.url