The csv342 version of DictReader cannot accept a list of CSV lines, though the built in version in both Python 2 and Python 3 can do so. If you're interested in accepting patches, I could submit one ...
Yes, I'm aware there are duplicate fieldnames (part of the "convoluted"), and also that you can't have duplicate keys in Dicts. I was having a forest-for-the-trees moment in not joining those two ...