How to solve the problem with starting the Bot with the aiogram library?

Question

Python

Hello. Wrote the following test bot on aiogram:

import logging
from aiogram import Bot, Dispatcher, executor, types

API_TOKEN ='Указан мой токен'
logging.basicConfig(level=logging.INFO)

bot = Bot(token=API_TOKEN)
dp = Dispatcher(bot)

@dp.message_handler(commands =['start, help'])
async def send_welcome(message: types.Message):

  await message.reply("hi\nI'm aiobot..")

@dp.message_handler()
async def echo(message: types.Message):
  
  await message.answer(message.text)

if __name__ == '__main__':
  executor.start_polling(dp, skip_updates=True)

And when I run it I get the following error:

C:\AIOGRAM\myles>python bot.py
Traceback (most recent call last):
File "C:\Users\maxim\AppData\Local\Programs\Python\Python38-32\lib\site -packages\aiogram\utils\executor.py", line 305, in start_polling
loop.run_until_complete(self._startup_polling())
AttributeError: 'NoneType' object has no attribute 'run_until_complete'

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
File "bot.py", line 33, in
executor.start_polling(dp, skip_updates=True)
File "C:\Users\maxim\AppData\Local\Programs\Python\Python38-32\ lib\site-packages\aiogram\utils\executor.py", line 41,in start_polling
executor.start_polling(reset_webhook=reset_webhook, timeout=timeout, relax=relax, fast=fast)
File "C:\Users\maxim\AppData\Local\Programs\Python\Python38-32\lib\site-packages\aiogram\utils \executor.py", line 313, in start_polling
loop.run_until_complete(self._shutdown_polling())
AttributeError: 'NoneType' object has no attribute 'run_until_complete' This is the

first time I've encountered this. Previously, bots were launched, both on aiogram and on pytelegrambotapi.
How many I searched for the answer - nowhere even close did not find similar situations. The bot was launched both on the local machine and on the server - the error is the same.

Answer 1

On an older version of aiogram, everything works. Looks like an update issue.

Answer 2

faced a similar problem
Above in the comment is true, aiogram 2.10 produces such errors Solved
by removing 2.10 and installing 2.9