code: def init_contexts(self, shared=None):
      self.personas_list = get_personas(opt=self.opt, shared=shared)
  
imports: from typing import Optional
  from parlai.core.params import ParlaiParser
  from parlai.core.opt import Opt
  from parlai.core.worlds import create_task
  from parlai.agents.fixed_response.fixed_response import FixedResponseAgent
  from parlai.tasks.self_chat.worlds import SelfChatWorld
  from parlai.tasks.interactive.worlds import InteractiveWorld
  import random
label_desc: Use image node_id 3 for calling the InteractiveWorld obj's underlying member method code with example usage: obj.init_contexts(shared) without return types