diff --git a/flask/helpers.py b/flask/helpers.py
index d24dde6b..a302995c 100644
--- a/flask/helpers.py
+++ b/flask/helpers.py
@@ -26,6 +26,7 @@ from functools import update_wrapper
 
 from werkzeug.datastructures import Headers
 from werkzeug.exceptions import NotFound
+import six
 
 # this was moved in 0.7
 try:
@@ -128,7 +129,7 @@ def stream_with_context(generator_or_function):
     # pushed.  This item is discarded.  Then when the iteration continues the
     # real generator is executed.
     wrapped_g = generator()
-    wrapped_g.next()
+    six.advance_iterator(wrapped_g)
     return wrapped_g
 
 
diff --git a/flask/sessions.py b/flask/sessions.py
index 3746da7f..b8e37014 100644
--- a/flask/sessions.py
+++ b/flask/sessions.py
@@ -85,7 +85,7 @@ class TaggedJSONSerializer(object):
         def object_hook(obj):
             if len(obj) != 1:
                 return obj
-            the_key, the_value = obj.iteritems().next()
+            the_key, the_value = six.advance_iterator(obj.iteritems())
             if the_key == ' t':
                 return tuple(the_value)
             elif the_key == ' u':
diff --git a/flask/testsuite/helpers.py b/flask/testsuite/helpers.py
index fdf2d89f..5604f85f 100644
--- a/flask/testsuite/helpers.py
+++ b/flask/testsuite/helpers.py
@@ -18,6 +18,7 @@ from logging import StreamHandler
 from StringIO import StringIO
 from flask.testsuite import FlaskTestCase, catch_warnings, catch_stderr
 from werkzeug.http import parse_cache_control_header, parse_options_header
+import six
 
 
 def has_encoding(name):
@@ -507,7 +508,7 @@ class StreamingTestCase(FlaskTestCase):
             def close(self):
                 called.append(42)
             def next(self):
-                return self._gen.next()
+                return six.advance_iterator(self._gen)
         @app.route('/')
         def index():
             def generate():