diff --git a/www/conservancy/middleware.py b/www/conservancy/middleware.py
index 8f714f5c28e8a04c4a8e40d5371c85bbb8750d73..cfb6eb38ff763b74fa07c3cac49c829eb7f26c3f 100644
--- a/www/conservancy/middleware.py
+++ b/www/conservancy/middleware.py
@@ -1,3 +1,4 @@
+from future.utils import raise_
 from django import http
 from django.conf import settings
 from django.utils.cache import patch_response_headers
@@ -27,13 +28,13 @@ class ForceCanonicalHostnameMiddleware(object):
         if settings.APPEND_SLASH and (old_url[1][-1] != '/') and ('.' not in old_url[1].split('/')[-1]):
             new_url[1] = new_url[1] + '/'
             if settings.DEBUG and request.method == 'POST':
-                raise RuntimeError, "You called this URL via POST, but the URL doesn't end in a slash and you have APPEND_SLASH set. Django can't redirect to the slash URL while maintaining POST data. Change your form to point to %s%s (note the trailing slash), or set APPEND_SLASH=False in your Django settings." % (new_url[0], new_url[1])
+                raise_(RuntimeError, "You called this URL via POST, but the URL doesn't end in a slash and you have APPEND_SLASH set. Django can't redirect to the slash URL while maintaining POST data. Change your form to point to %s%s (note the trailing slash), or set APPEND_SLASH=False in your Django settings." % (new_url[0], new_url[1]))
         # Strip trailing index.html
         if new_url[1].endswith('/index.html'):
             new_url[1] = new_url[1][:new_url[1].rfind('index.html')]
         # Consult redirect table (if exists)
         if hasattr(settings, "REDIRECT_TABLE"):
-            if settings.REDIRECT_TABLE.has_key(new_url[1]):
+            if new_url[1] in settings.REDIRECT_TABLE:
                 new_url[1] = settings.REDIRECT_TABLE[new_url[1]]
         if new_url != old_url:
             # Force canonical hostname