Move itertools izip() code to builtins as zip().  Complete the renaming.
diff --git a/Lib/test/test_heapq.py b/Lib/test/test_heapq.py
index 7969d6e..1e21736 100644
--- a/Lib/test/test_heapq.py
+++ b/Lib/test/test_heapq.py
@@ -260,7 +260,7 @@
     def __next__(self):
         raise StopIteration
 
-from itertools import chain, map
+from itertools import chain
 def L(seqn):
     'Test multiple tiers of iterators'
     return chain(map(lambda x:x, R(Ig(G(seqn)))))