So, after doing some research I've come to the conclusion that this most likely is a bot licensed by Fast to Denodo. It looks like Fast has licensed bots to a handful of organisations, mostly for scientific purposes.
Denodo is a company specialising in natural language search applications, quite an interesting field. BTW: thanks for the link to the article, richmc, had it bookmarked long ago but never got around reading it.
As Fast is one of the engines which has NLP (Natural Language Processing) implemented to a certain degree there is a chance that some tech transfer between the two companies is involved, though I don't have any information in that regard.
The Py part of the UA seems to indicate the bot is either programmed in Python. Or it's a bot dedicated to crawl Python files, which I find rather unlikely.