I've written a program that uses PyQt4, Matplotlib, and cElementTree to parse and extract data from an XML file.  After selecting a file from a PyQt dialog the main program directly initializes my own XML document class  (which was imported from another file).  This class has a method that parses the file name passed during the class initialization.  In the process of parsing the XML file a number of attributes for the XML document class are initialized.  All of this runs without fail in python, however, whenever I try to access the attributes of the XML document class after bundling with py2exe I continue to get the error:

TypeError: 'NoneType' object is unsubscriptable

It seems as though the method associated with the XML document class is not being called and/or the class attributes are not being updated.  Is there a solution or a work around?  I'm losing my hair faster than normal on this one.  Any help would be greatly appreciated. 

Cheers,

Brian