def next_prepared_build_scheduler(self):
        build = self._builds_waiting_for_slaves.get()
        build_scheduler = self._scheduler_pool.get(build)
        return build_scheduler
Get the scheduler for the next build that has successfully completed build preparation.
dataset/ETHPy150Open box/ClusterRunner/app/master/build_request_handler.py/BuildRequestHandler.next_prepared_build_scheduler