code: def is_ophint_converted(graph_def):
      if graph_def is None:
          raise ValueError("Must provide the graph_def.")
      ophint_converted = False
      for node in graph_def.node:
          attr = node.attr
          if OpHint.FUNCTION_INPUT_INDEX_ATTR in attr:
              ophint_converted = True
              break
      return ophint_converted
  
imports: import collections
  import copy
  import json
  import uuid
  from tensorflow.core.framework import attr_value_pb2
  from tensorflow.core.framework import graph_pb2
  from tensorflow.core.framework import node_def_pb2
  from tensorflow.python.framework import dtypes
  from tensorflow.python.framework import ops
  from tensorflow.python.framework import tensor_util
  from tensorflow.python.framework.graph_util_impl import _bfs_for_reachable_nodes
  from tensorflow.python.framework.graph_util_impl import _extract_graph_summary
  from tensorflow.python.ops import array_ops
  from tensorflow.python.util import compat
  from tensorflow.python.util import deprecation
  from tensorflow.python.util.all_util import remove_undocumented
  from tensorflow.python.util.tf_export import tf_export
label_desc: Use image node_id 14 for calling a global function with example usage: is_ophint_converted(graph_def) and returns: ophint_converted