class_docstr: Abstract base class for training hooks.
    
docstr: Returns true if and only if the current process is the chief.
  This is used for distributed training.
docstr_tok: ["Returns","true","if","and","only","if","the","current","process","is","the","chief",".","This","is","used","for","distributed","training","."]
code: def is_chief(self):
      """Returns true if and only if the current process is the chief.
      This is used for distributed training.
      """
      return self._run_config.is_chief
  
imports: from __future__ import absolute_import
  from __future__ import division
  from __future__ import print_function
  from __future__ import unicode_literals
  import abc
  import os
  import numpy
  import six
  import yaml
  import tensorflow
  from tensorflow.python.training.basic_session_run_hooks import SecondOrStepTimer
  from tensorflow.python.training import session_manager
  from tensorflow.python.client import timeline
  from tensorflow import gfile
  from seq2seq.configurable import Configurable, abstractstaticmethod
  from seq2seq import graph_utils, global_vars
label_desc: Use image node_id 3 for calling the TrainingHook obj's underlying member method code with example usage: obj.is_chief() and returns: self