code: def get_contexts(self):
      random.seed()
      topic = random.choice(self.topic_list)
      return [topic, topic]
  
imports: from typing import Optional
  from parlai.core.opt import Opt
  from copy import deepcopy
  import json
  import random
  import os
  import string
  from parlai.core.params import ParlaiParser
  from parlai.core.agents import create_agent
  from parlai.core.message import Message
  from parlai.core.worlds import DialogPartnerWorld, validate
  from parlai.tasks.wizard_of_wikipedia.agents import TOKEN_KNOWLEDGE, TOKEN_END_KNOWLEDGE
  from parlai.tasks.self_chat.worlds import SelfChatWorld
  from parlai.utils.misc import warn_once
  from .build import build
  from projects.wizard_of_wikipedia.knowledge_retriever.knowledge_retriever import KnowledgeRetrieverAgent
label_desc: Use image node_id 2 for calling the SelfChatWorld obj's underlying member method code with example usage: obj.get_contexts() and returns: list