code: def checkpoint_exists(path):
      return (
          tf.gfile.Exists(path)
          or tf.gfile.Exists(path + ".meta")
          or tf.gfile.Exists(path + ".index")
      )
  
file_path: tensor2tensor/tensor2tensor/utils/avg_checkpoints.py
imports: from __future__ import absolute_import
  from __future__ import division
  from __future__ import print_function
  import os
  import numpy
  import six
  from six.moves import zip
  import tensorflow.compat.v1
label_desc: Use image node_id 1 for calling a global function with example usage: checkpoint_exists(path) and returns: unknown