class_docstr: Text logger of training information.
  
  Arguments
  ---------
  save_file : str
      The file to use for logging train information.
  precision : int
      Number of decimal places to display. Default 2, example: 1.35e-5.
  summary_fns : dict of str:function pairs
      Each summary function should take a list produced as output
      from a training/validation pass and summarize it to a single scalar.
docstr: Convert all stats to a single string summary
docstr_tok: ["Convert","all","stats","to","a","single","string","summary"]
code: def _stats_to_string(self, stats, dataset=None):
      """Convert all stats to a single string summary"""
      return ", ".join(
          [
              self._item_to_string(k, v, dataset)
              for k, v in stats.items()
          ]
      )
  
imports: import logging
  import torch
  import os
  from speechbrain.utils.distributed import main_process_only, if_main_process
label_desc: Use image node_id 3 for calling the FileTrainLogger obj's underlying member method code with example usage: obj._stats_to_string(stats, dataset) and returns: str