Creating several ParsedXML from a string

Hi,

Given one XML document, I need to create several ParsedXMLs.  How to do 
this?

I tried to hack by:
* creating a DOM tree
* for each subtree of interest,
  - [...].manage_addProduct['ParsedXML'].manage_addParsedXML(subtree id)
  - [...][node id].initFromDOMDocument(subtree)

This doesn't work, nonwithstanding the fact that initFromDOMDocument is 
a private method.  The DOM tree is created with minidom.parseString; 
perhaps this would be better using ExpatBuilder (but then, I've not 
found all the classes and modules to allow abusively :)

What's a proper way to do this?

Thanks,

Yves