[Zope-dev] Explore the Zope objects hierarchy

Hi I have a problem. I would to generate a Python module that can explore the Zope objects hierarchy. I have created a ZClass like a DTMLDocument with some differences and so I need to replace a very large number of DTMLDocuments with instances of my ZClass, manteining the contents of the documents (body and properties). I want to do that by an automatic procedure using Python. I think is important to read and update the content of the file data.fs, but I don't know how I can do it. What is the format of the file ? Is there any python module for this problem ? Where can I find it ? Thanks Luca