class_docstr: Version of BaseModelChatWorld for chatting without images.
  
  Has support for features that are currently not supported by the image-chat version
  of this task, like personas and BST-style seed utterances.
class_docstr_tok: ["Version","of","BaseModelChatWorld","for","chatting","without","images",".","Has","support","for","features","that","are","currently","not","supported","by","the","image-chat","version","of","this","task",",","like","personas","and","BST-style","seed","utterances","."]
docstr: Apply acceptability checking params specific to BST-style conversation.
  
  The BST mode starts the conversation with two previous utterances, so there
  should be no new greeting. Also, the first human response is one of the previous
  utterances, so it shouldn't get checked.
docstr_tok: ["Apply","acceptability","checking","params","specific","to","BST-style","conversation",".","The","BST","mode","starts","the","conversation","with","two","previous","utterances",",","so","there","should","be","no","new","greeting",".","Also",",","the","first","human","response","is","one","of","the","previous","utterances",",","so","it","should","n't","get","checked","."]
code: def _prepare_acceptability_checking(
      self,
  ) -> Tuple[List[str], List[str]]:
      """
      Apply acceptability checking params specific to BST-style conversation.
  
      The BST mode starts the conversation with two previous utterances, so there
      should be no new greeting. Also, the first human response is one of the previous
      utterances, so it shouldn't get checked.
      """
      human_messages = [
          message["text"]
          for message in self.dialog
          if message["id"] == "YOU"
      ]
      violation_types = ["min_words", "all_caps", "exact_match"]
      if self.opt["conversation_start_mode"] == "blended_skill_talk":
          violation_types.append("penalize_greetings")
          # human_messages = human_messages[1:]
      return human_messages, violation_types
  
file_path: ParlAI/parlai/crowdsourcing/projects/multisession_chat/human_eval/worlds.py
imports: import time
  from typing import Any, Dict, List, Tuple
  from parlai.core.worlds import validate
  from parlai.crowdsourcing.tasks.model_chat.utils import Compatibility
  from parlai.crowdsourcing.tasks.model_chat.worlds import BaseModelChatWorld, get_bot_worker, get_world_params
  import parlai.utils.logging
label_desc: Use image node_id 4 for calling the ModelChatWorld obj's underlying member method code with example usage: obj._prepare_acceptability_checking() and returns: human_messages,  violation_types