telethon fails on python on GAE platform - telethon

Question

I would appreciate if somebody could shine a light on this, I try to setup a simple telegram bot to be run on Python on Google App Engine with telethon libarary, but failed. Was this approach workable ?
after gcloud app deploy, I receive the Internal Server Error from browser.
the problem does not happen if I remarked the following line:
client = TelegramClient(phone, api_id, api_hash)
main.py
from flask import Flask, request
import datetime
import time
import asyncio
from telethon import TelegramClient, events, sync
app = Flask(__name__)
api_id = xxxxxxxx
api_hash = 'xxxxxxxxxxxxxxxxxxxxxxxx'
phone = '+xxxxxxxxxxxx'
#app.route('/', methods=['GET'])
def hello():
reqaction = request.args.get('action', 'connect')
client = TelegramClient(phone, api_id, api_hash)
if __name__ == '__main__':
app.run(host='localhost', port=8080, debug=True)
below is the logging:
Traceback (most recent call last):
File "/env/lib/python3.7/site-packages/flask/app.py", line 2446, in wsgi_app
response = self.full_dispatch_request()
File "/env/lib/python3.7/site-packages/flask/app.py", line 1951, in full_dispatch_request
rv = self.handle_user_exception(e)
File "/env/lib/python3.7/site-packages/flask/app.py", line 1820, in handle_user_exception
reraise(exc_type, exc_value, tb)
File "/env/lib/python3.7/site-packages/flask/_compat.py", line 39, in reraise
raise value
File "/env/lib/python3.7/site-packages/flask/app.py", line 1949, in full_dispatch_request
rv = self.dispatch_request()
File "/env/lib/python3.7/site-packages/flask/app.py", line 1935, in dispatch_request
return self.view_functions[rule.endpoint](**req.view_args)
File "/srv/main.py", line 95, in hello
client = TelegramClient(phone, api_id, api_hash) ;
File "lib/telethon/client/telegrambaseclient.py", line 230, in __init__
self._loop = loop or asyncio.get_event_loop()
File "/opt/python3.7/lib/python3.7/asyncio/events.py", line 644, in get_event_loop
% threading.current_thread().name)
RuntimeError: There is no current event loop in thread 'ThreadPoolExecutor-0_0'.
Many thanks in advance for your giude and help :)