I'm helping some manufacturing companies link up their EDI systems using the GS1 XML specs (this is an international spec for companies to pass things like purchase-orders, invoices, barcodes etc. http://en.wikipedia.org/wiki/GS1).
There are lots of Big Iron solutions, and lots of Java and C# solutions, and even a couple in PHP. But I haven't found any projects in Python.
Have you tried this, and can you offer any war stories?
I worked with GS1 XML specs. Nothing special, just very baroque. for edi I use bots (http://bots.sourceforge.net) for AS2 (bots does not do AS2) http://opensource.mendelson-e-c.com/