code: def get_chosen_topic_passages(self, chosen_topic):
      retrieved_txt_format = []
      retrieved_txt_format_no_title = []
      if chosen_topic in self.wiki_map:
          retrieved_txt = self.wiki_map[chosen_topic]
          retrieved_txts = retrieved_txt.split("\n")
  
          if len(retrieved_txts) > 1:
              combined = " ".join(retrieved_txts[2:])
              sentences = self.sent_tok.tokenize(combined)
              total = 0
              for sent in sentences:
                  if total >= 10:
                      break
                  if len(sent) > 0:
                      if self.add_token_knowledge:
                          delim = " " + TOKEN_KNOWLEDGE + " "
                      else:
                          delim = " "
                      retrieved_txt_format.append(
                          delim.join([chosen_topic, sent])
                      )
                      retrieved_txt_format_no_title.append(sent)
                      total += 1
  
      if len(retrieved_txt_format) > 0:
          passages = "\n".join(retrieved_txt_format)
          passages_no_title = "\n".join(retrieved_txt_format_no_title)
      else:
          passages = ""
          passages_no_title = ""
  
      return passages, passages_no_title
  
imports: from typing import Optional
  from parlai.core.params import ParlaiParser
  from parlai.core.opt import Opt
  from parlai.core.agents import Agent, create_agent, create_agent_from_shared
  from parlai.core.torch_ranker_agent import TorchRankerAgent
  from parlai.tasks.wizard_of_wikipedia.agents import TOKEN_KNOWLEDGE
  from parlai.zoo.wizard_of_wikipedia.knowledge_retriever import download
  import json
  import os
label_desc: Use image node_id 7 for calling the KnowledgeRetrieverAgent obj's underlying member method code with example usage: obj.get_chosen_topic_passages(chosen_topic) and returns: passages,  passages_no_title