code: def test_read_write(self):
      ioctx = IOContext(self.test_dir, None, 0, None)
      writer = JsonWriter(
          self.test_dir,
          ioctx,
          max_file_size=5000,
          compress_columns=["obs"],
      )
      for i in range(100):
          writer.write(make_sample_batch(i))
      reader = JsonReader(self.test_dir + "/*.json")
      seen_a = set()
      seen_o = set()
      for i in range(1000):
          batch = reader.next()
          seen_a.add(batch["actions"][0])
          seen_o.add(batch["obs"][0])
      self.assertGreater(len(seen_a), 90)
      self.assertLess(len(seen_a), 101)
      self.assertGreater(len(seen_o), 90)
      self.assertLess(len(seen_o), 101)
  
imports: import glob
  import json
  import numpy
  import os
  import random
  import shutil
  import tempfile
  import unittest
  import ray
  from ray.tune.registry import register_env, register_input, registry_get_input, registry_contains_input
  from ray.rllib.algorithms.algorithm_config import AlgorithmConfig
  from ray.rllib.algorithms.pg import PGConfig
  from ray.rllib.algorithms.ppo import PPOConfig
  from ray.rllib.examples.env.multi_agent import MultiAgentCartPole
  from ray.rllib.offline import IOContext, JsonWriter, JsonReader, InputReader, ShuffledInput, DatasetWriter
  from ray.rllib.offline.json_reader import from_json_data
  from ray.rllib.offline.json_writer import _to_json_dict, _to_json
  from ray.rllib.policy.sample_batch import SampleBatch, convert_ma_batch_to_sample_batch
  from ray.rllib.utils.test_utils import framework_iterator
label_desc: Use image node_id 7 for calling the JsonIOTest obj's underlying member method code with example usage: obj.test_read_write() without return types