Breaking ground for PEP 3137 implementation:

Get rid of buffer().  Use memoryview() in its place where possible.
In a few places, do things a bit different, because memoryview()
can't slice (yet).
diff --git a/Lib/test/test_io.py b/Lib/test/test_io.py
index 5c30e50..644593d 100644
--- a/Lib/test/test_io.py
+++ b/Lib/test/test_io.py
@@ -251,7 +251,7 @@
 
     def test_array_writes(self):
         a = array.array('i', range(10))
-        n = len(buffer(a))
+        n = len(memoryview(a))
         f = io.open(test_support.TESTFN, "wb", 0)
         self.assertEqual(f.write(a), n)
         f.close()