ever considered doing the mapping this way?
window = [
["item", {'k1': 'v1', 'k2': 'v2'],
["otheritem", {'k1n': 'v1n', 'k2n': 'v2n'}]
]
it is as simple as it gets: for 1:1 mapping from XML, list of
Attributes becomes py List.
the list of Properties of an attribute becomes a py Dictionary
ps. you can do tuples instead of lists if immutable is ok.