# Chapter 5/thread_pool.py
import time
import queue
import typing as T
from threading import Thread, current_thread

Callback = T.Callable[..., None]
Task = T.Tuple[Callback, T.Any, T.Any]
TaskQueue = queue.Queue

class Worker(Thread):
    def __init__(self, tasks: queue.Queue[Task]):
        super().__init__()
        self.tasks = tasks

    def run(self) -> None: