Analgen

import time
import random

token ='YOU TOKEN'

import vkbee
import asyncio

loop = asyncio.get_event_loop()
vk_s = vkbee.VkApi(token, loop=loop)
async def main(loop):
	_trynum = 0
	while True:
		_name = ''

		for x in range(random.randint(23,24)):
			_name = _name + random.choice(list('123456789qwertyuiopasdfghjklzxcvbnmQWERTYUIOPASDFGHJKLZXCVBNM_/'))
		ok= 'vk.me/join/{0}'.format(_name)
		a =await vkbee.VkApi.call(vk_s,'messages.getChatPreview',{'link': ok})
		if 'error' in a:
			text = '[{0}]not valid  ({1})'.format(_trynum,ok)
			print (text)
			_trynum +=1
			time.sleep(0.5)
		else:
			print (ok)
			input('valid')

asyncio.get_event_loop().run_until_complete(main(loop))