class_docstr: Logs trial results in json format.
  
  Also writes to a results file and param.json file when results or
  configurations are updated. Experiments must be executed with the
  JsonLogger to be compatible with the ExperimentAnalysis tool.
code: def _init(self):
      self.update_config(self.config)
      local_file = os.path.join(self.logdir, EXPR_RESULT_FILE)
      self.local_out = open(local_file, "a")
  
imports: import json
  import logging
  import numpy
  import os
  from typing import TYPE_CHECKING, Dict, TextIO
  from ray.air.constants import EXPR_PARAM_FILE, EXPR_PARAM_PICKLE_FILE, EXPR_RESULT_FILE
  import ray.cloudpickle
  from ray.tune.logger.logger import _LOGGER_DEPRECATION_WARNING, Logger, LoggerCallback
  from ray.tune.utils.util import SafeFallbackEncoder
  from ray.util.annotations import Deprecated, PublicAPI
label_desc: Use image node_id 1 for calling the JsonLogger obj's underlying member method code with example usage: obj._init() without return types