'Commit a two phase transaction on the given connection.
:param connection: a :class:`.Connection`.
:param xid: xid
:param is_prepared: whether or not
:meth:`.TwoPhaseTransaction.prepare` was called.
:param recover: if the recover flag was passed.'

def do_commit_twophase(self, connection, xid, is_prepared=True, recover=False):

    raise NotImplementedError()
