code: def graphviz(self, groups=None):
      print("digraph G {")
      if groups is not None:
          for root, group in groups.items():
              print("")
              print(
                  (
                      "  subgraph",
                      "cluster_%s" % root.name.replace("/", "_"),
                      "{",
                  )
              )
              print(
                  ('  label = "%s"') % (root.pretty_name or root.name)
              )
              for node in group:
                  print(('    "%s"') % (node.pretty_name or node.name))
              print("  }")
      for node in self.nodes:
          for inp in node.inputs:
              print(
                  (
                      "  ",
                      '"' + (inp.pretty_name or inp.name) + '"',
                      " -> ",
                      '"' + (node.pretty_name or node.name) + '"',
                  )
              )
      print("}")
  
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 5 for calling the Graph obj's underlying member method code with example usage: obj.graphviz(groups) without return types