code: def get_bell_environment_variable() -> bool:
      """
      True if env variable is set to true (true, TRUE, True, 1).
      """
      value = os.environ.get("PROMPT_TOOLKIT_BELL", "true")
      return value.lower() in ("1", "true")
  
imports: from __future__ import annotations
  import os
  import signal
  import sys
  import threading
  from collections import deque
  from typing import Callable, ContextManager, Dict, Generator, Generic, TypeVar, Union
  from wcwidth import wcwidth
label_desc: Use image node_id 7 for calling a global function with example usage: get_bell_environment_variable() and returns: unknown