Specifically things like cluster.transactions() to create a transactions object. Also, single query txns, and the ClusterOptions need to have a TransactionConfig. Stuff like that. Note the sad config vs options thing. Oh well...
There is not a formal doc yet, but Java and Node both have done it. Also there's a google doc which should help.
|For Gerrit Dashboard: PYCBC-1291
|PYCBC-1291: Integrate transactions api into existing api