class_docstr: Get data from file cache directly.
code: def initialize_cache_info(self, info_filename):
      try:
          with FileReader(info_filename).open(textmode=True) as f:
              self._variables = []
              reader = csv.reader(f)
              for row in reader:
                  self._variables.append(row[0])
          self._cache_type = ".npy"
      except:
          self._cache_type = ".h5"
  
imports: import atexit
  import csv
  import os
  import threading
  from collections import OrderedDict, deque
  from time import sleep
  import numpy
  from nnabla.config import nnabla_config
  from nnabla.logger import logger
  from nnabla.utils.communicator_util import current_communicator
  from six.moves import queue
  from .data_source import DataSource
  from .data_source_loader import FileReader, load
label_desc: Use image node_id 5 for calling the CacheDataSource obj's underlying member method code with example usage: obj.initialize_cache_info(info_filename) without return types