docstr: Return our current LLMThought. Raise an error if we have no current
  thought.
docstr_tok: ["Return","our","current","LLMThought",".","Raise","an","error","if","we","have","no","current","thought","."]
code: def _require_current_thought(self) -> LLMThought:
      """Return our current LLMThought. Raise an error if we have no current
      thought.
      """
      if self._current_thought is None:
          raise RuntimeError("Current LLMThought is unexpectedly None!")
      return self._current_thought
  
imports: from __future__ import annotations
  import time
  from enum import Enum
  from typing import TYPE_CHECKING, Any, Dict, List, NamedTuple, Optional
  from langchain.callbacks.base import BaseCallbackHandler
  from langchain.schema import AgentAction, AgentFinish, LLMResult
  from streamlit.runtime.metrics_util import gather_metrics
label_desc: Use image node_id 2 for calling the StreamlitCallbackHandler obj's underlying member method code with example usage: obj._require_current_thought() and returns: self