combine_details blows up when there are duplicate details
combine_details refers to advance_iterator, which is an unknown name. This means that whenever getDetails is called for duplicate details (say, a parent with 'traceback' and a child with 'traceback'), then combine_details will raise an error that looks like this:
Traceback (most recent call last):
'foo-1': 'child-content',}, parent.
new_name = '%s-%d' % (name, advance_
NameError: global name 'advance_iterator' is not defined
I believe this to be a Critical bug.