class_docstr: Customed Graph class.
code: def __str__(self):
      info = ""
      for l_id, layer in enumerate(self.layers):
          if layer.is_delete is False:
              info += "id:%d " % l_id + str(layer) + "\n"
      return info
  
imports: import copy
  import json
  import random
  from enum import Enum, unique
label_desc: Use image node_id 6 for calling the Graph obj's underlying member method code with example usage: obj.__str__() and returns: info