How can I generate files in the old GO flat file format?

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The original GO flat file format is deprecated and will no longer be provided by the GO Consortium after 1st Aug 2009. If you still need to work with this file format GO provides a script obo2flat, it converts from the GO flat file format to the newer OBO format. obo2flat is a command-line, Java script that comes as part of the OBO-Edit package. For further instructions on how to use obo2flat, please see the OBO-Edit User Guide