def __init__(self, port, host, num_executors=10):
        self.port = port
        self.host = host
        self.is_alive = True
        self._slave_id = None
        self._num_executors = num_executors
        self._logger = log.get_logger(__name__)

        self._idle_executors = Queue(maxsize=num_executors)
        self.executors_by_id = {}
        for executor_id in range(num_executors):
            executor = SubjobExecutor(executor_id)
            self._idle_executors.put(executor)
            self.executors_by_id[executor_id] = executor

        self._master_url = None
        self._network = Network(min_connection_poolsize=num_executors)
        self._master_api = None  # wait until we connect to a master first

        self._project_type = None  # this will be instantiated during build setup
        self._current_build_id = None
        self._build_teardown_coin = None
        self._base_executor_index = None
:param port: The port number the slave service is running on
dataset/ETHPy150Open box/ClusterRunner/app/slave/cluster_slave.py/ClusterSlave.__init__