code: def __getitem__(self, index):
      if isinstance(index, str):
          return self.name_map[index]
      elif isinstance(index, Node):
          return self.name_map[index.name]
      else:
          raise Exception("Unsupported index for Graph", type(index))
  
imports: import numpy
  import tensorflow
  import lucid.modelzoo.vision_models
  import lucid.optvis.objectives
  import lucid.optvis.param
  import lucid.optvis.render
  from lucid.misc.io import show, load
  from lucid.misc.io.showing import _image_url, _display_html
  from collections import defaultdict
label_desc: Use image node_id 4 for calling the Graph obj's underlying member method code with example usage: obj.__getitem__(index) and returns: self, self