Remove all \bcode / \ecode cruft; this is no longer needed.  See previous
checkin of myformat.sty.

Change "\renewcommand{\indexsubitem}{(...)}" to "\setindexsubitem{(...)}"
everywhere.

Some other minor nits that I happened to come across.
diff --git a/Doc/lib/libtraceback.tex b/Doc/lib/libtraceback.tex
index 4fcc4d1..2bdd22b 100644
--- a/Doc/lib/libtraceback.tex
+++ b/Doc/lib/libtraceback.tex
@@ -2,7 +2,7 @@
 \label{module-traceback}
 \stmodindex{traceback}
 
-\renewcommand{\indexsubitem}{(in module traceback)}
+\setindexsubitem{(in module traceback)}
 
 This module provides a standard interface to format and print stack
 traces of Python programs.  It exactly mimics the behavior of the