code: def _setup_graph(self):
      NR_PROC = min(multiprocessing.cpu_count() // 2, 20)
      self.pred_funcs = [
          self.trainer.get_predictor(
              self.input_names, self.output_names
          )
      ] * NR_PROC
  
file_path: tensorpack/examples/A3C-Gym/common.py
imports: import multiprocessing
  import numpy
  import random
  import time
  from six.moves import queue
  from tensorpack.callbacks import Callback
  from tensorpack.utils import logger, get_tqdm
  from tensorpack.utils.concurrency import ShareSessionThread, StoppableThread
  from tensorpack.utils.stats import StatCounter
label_desc: Use image node_id 2 for calling the Evaluator obj's underlying member method code with example usage: obj._setup_graph() without return types