tg_app/try_telethon.py

from telethon import TelegramClient


with open('data/tg_api_id.txt') as f:
    api_id = f.read().strip()

with open('data/tg_app_api_hash.txt') as f:
    api_hash = f.read().strip()

with TelegramClient('data/session.session', api_id, api_hash) as client:
    client.loop.run_until_complete(client.send_message('me', 'Hello, myself!'))