class_docstr: An multithreaded online async predictor which runs a list of OnlinePredictor.
  It would do an extra batching internally.
class_docstr_tok: ["An","multithreaded","online","async","predictor","which","runs","a","list","of","OnlinePredictor",".","It","would","do","an","extra","batching","internally","."]
code: def start(self):
      if self._need_default_sess:
          assert tfv1.get_default_session() is not None, (
              "Not session is bind to predictors, "
              "MultiThreadAsyncPredictor.start() has to be called under a default session!"
          )
      for t in self.threads:
          t.start()
  
imports: import multiprocessing
  import numpy
  from concurrent.futures import Future
  import tensorflow
  from six.moves import queue, range
  from ..compat import tfv1
  from ..tfutils.model_utils import describe_trainable_vars
  from ..utils import logger
  from ..utils.concurrency import DIE, ShareSessionThread, StoppableThread
  from .base import AsyncPredictorBase, OfflinePredictor, OnlinePredictor
label_desc: Use image node_id 2 for calling the MultiThreadAsyncPredictor obj's underlying member method code with example usage: obj.start() without return types