Change all the function attributes from func_* -> __*__.  This gets rid
of func_name, func_dict and func_doc as they already exist as __name__,
__dict__ and __doc__.
diff --git a/Lib/dis.py b/Lib/dis.py
index 385c19d..90544f4 100644
--- a/Lib/dis.py
+++ b/Lib/dis.py
@@ -20,8 +20,8 @@
         return
     if hasattr(x, 'im_func'):
         x = x.im_func
-    if hasattr(x, 'func_code'):
-        x = x.func_code
+    if hasattr(x, '__code__'):
+        x = x.__code__
     if hasattr(x, '__dict__'):
         items = x.__dict__.items()
         items.sort()