List of non-default commodities?

[Derek Atkins]

Is there a convenient way to get the list of all non-default
commodities?  What I want to do is grab the list of all commodities
defined within book, but I don't need the commodities that are
pre-defined in Gnucash.

Unfortunately the commodity_table contains all of them, so walking
through that gives me everything.  That's not what I want.

Any ideas?

-derek
-- 
       Derek Atkins, SB '93 MIT EE, SM '95 MIT Media Laboratory
       Member, MIT Student Information Processing Board  (SIPB)
       URL: http://web.mit.edu/warlord/    PP-ASEL-IA     N1NWH
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