[py3] Renamed next to __next__ in iterators.

See PEP 3114. `next` is retained as an alias for Python 2.

django/core/serializers/base.py

@@ -136,10 +136,12 @@ class Deserializer(object):
     def __iter__(self):
         return self
 
-    def next(self):
+    def __next__(self):
         """Iteration iterface -- return the next item in the stream"""
         raise NotImplementedError
 
+    next = __next__             # Python 2 compatibility
+
 class DeserializedObject(object):
     """
     A deserialized model.

django/core/serializers/xml_serializer.py

@@ -154,13 +154,15 @@ class Deserializer(base.Deserializer):
         self.event_stream = pulldom.parse(self.stream)
         self.db = options.pop('using', DEFAULT_DB_ALIAS)
 
-    def next(self):
+    def __next__(self):
         for event, node in self.event_stream:
             if event == "START_ELEMENT" and node.nodeName == "object":
                 self.event_stream.expandNode(node)
                 return self._handle_object(node)
         raise StopIteration
 
+    next = __next__             # Python 2 compatibility
+
     def _handle_object(self, node):
         """
         Convert an <object> node to a DeserializedObject.