code: def _is_variable(x):
      return isinstance(
          x, variables.Variable
      ) or resource_variable_ops.is_resource_variable(x)
  
imports: from collections import abc
  import os
  import time
  from tensorflow.python.checkpoint import checkpoint_management
  from tensorflow.python.distribute import distribute_lib
  from tensorflow.python.framework import ops
  from tensorflow.python.ops import io_ops
  from tensorflow.python.ops import resource_variable_ops
  from tensorflow.python.ops import variable_scope
  from tensorflow.python.ops import variables
  from tensorflow.python.platform import gfile
  from tensorflow.python.platform import tf_logging
  from tensorflow.python.training import py_checkpoint_reader
  from tensorflow.python.training.saving import saveable_object_util
  from tensorflow.python.util.tf_export import tf_export
label_desc: Use image node_id 11 for calling a global function with example usage: _is_variable(x) and returns: unknown