diff --git a/doc/conf.py b/doc/conf.py
index 33f1eb180e..4fbc981a4a 100644
--- a/doc/conf.py
+++ b/doc/conf.py
@@ -55,9 +55,12 @@ class Mock(object):
     def __iter__(self):
         return self
 
-    def next(self):
+    def __next__(self):
         raise StopIteration
 
+    # For Python 2
+    next = __next__
+
 # pylint: enable=R0903
 
 MOCK_MODULES = [