code: def read_summary_values(self, _step):
      return self._disk_stats()
  
file_path: guildai/guild/plugins/disk.py
imports: import os
  import platform
  import re
  import sys
  import time
  from guild.plugins.summary_util import SummaryPlugin
label_desc: Use image node_id 3 for calling the DiskPlugin obj's underlying member method code with example usage: obj.read_summary_values(_step) and returns: self