Remove weakref from setup.py now that it is builtin.
diff --git a/setup.py b/setup.py
index 7d5d30c..36257ed 100644
--- a/setup.py
+++ b/setup.py
@@ -453,7 +453,7 @@
         #
 
         # Some modules that are normally always on:
-        exts.append( Extension('_weakref', ['_weakref.c']) )
+        #exts.append( Extension('_weakref', ['_weakref.c']) )
 
         # array objects
         exts.append( Extension('array', ['arraymodule.c']) )