code: def _load_graphdef_protobuf(handle, **kwargs):
      """Load GraphDef from a binary proto file."""
      # as_graph_def
      graph_def = tf.GraphDef.FromString(handle.read())
  
      # check if this is a lucid-saved model
      # metadata = modelzoo.util.extract_metadata(graph_def)
      # if metadata is not None:
      #   url = handle.name
      #   return modelzoo.vision_base.Model.load_from_metadata(url, metadata)
  
      # else return a normal graph_def
      return graph_def
  
imports: import io
  import lzma
  import os
  import json
  import logging
  import pickle
  import numpy
  import PIL.Image
  import tensorflow
  from concurrent.futures import ThreadPoolExecutor, as_completed
  from google.protobuf.message import DecodeError
  from lucid.misc.io.reading import read_handle
  from lucid.misc.io.scoping import current_io_scopes, set_io_scopes
  from lucid.misc.io.saving import nullcontext
label_desc: Use image node_id 6 for calling a global function with example usage: _load_graphdef_protobuf(handle) and returns: graph_def