diff --git a/www/conservancy/bsoup.py b/www/conservancy/bsoup.py
index 28ccdd08826e017d0e1c0303efd5a4ea2c9d66f0..de0107c0eebc853fc0d7154cbd6a0e7fc4de89e4 100644
--- a/www/conservancy/bsoup.py
+++ b/www/conservancy/bsoup.py
@@ -1,5 +1,6 @@
 # -*- encoding: utf-8 -*-
 
+from builtins import object
 import io
 import itertools
 import re
@@ -105,7 +106,7 @@ class BeautifulSoup(bs4.BeautifulSoup):
         return self.find_all(self.is_video_source, src=True)
 
 
-class SoupModelMixin:
+class SoupModelMixin(object):
     """Mixin for models to parse HTML with BeautifulSoup.
 
     Classes that use this mixin must define `SOUP_ATTRS`, a list of strings