def async(func):
  def wrapper(*args, **kwargs):
    thr = Thread(target = func, args = args, kwargs = kwargs)
    thr.start()
  return wrapper

@async
def del_old_pictures():
  global img_del_delay, need_exit
  while True:
    now = time.time()
    filelist = os.listdir(del_folder)
    for fn in filelist:
      fpfn = os.path.join(del_folder, fn)
      if fn.endswith(".sh"):
        age = now - os.stat(fpfn).st_mtime
        if age>img_del_delay:
          os.system(fpfn)
    if need_exit:
      break
    time.sleep(60)
    if need_exit:
      break

users = {}

@bot.message_handler(commands="spam")
def spam(m):
 now = datetime.now()
 if (now - users[m.from_user.id]).seconds / 1000 > 10.0:
  bot.send_message(m.chat.id, "ok")
  users[m.from_user.id] = now
 else:
  bot.send_message(m.chat.id, "spammer")