@utils.decorator<EOL>def transactional_async(func, args, kwds, **options):
options.setdefault('<STR_LIT>', datastore_rpc.TransactionOptions.ALLOWED)<EOL>if args or kwds:<EOL><INDENT>return transaction_async(lambda: func(*args, **kwds), **options)<EOL><DEDENT>return transaction_async(func, **options)<EOL>
The async version of @ndb.transaction.