Telegram Channel Listener with Python - https://python.plainenglish.io/telegram-channel-listener-with-python-8176ebe3c89b

main.py

# Code from  https://python.plainenglish.io/telegram-channel-listener-with-python-8176ebe3c89b

import configparser
import json
import re
from telethon.errors import SessionPasswordNeededError
from telethon import TelegramClient, events, sync
from telethon.tl.functions.messages import (GetHistoryRequest)
from telethon.tl.types import (
PeerChannel
)

api_id = <YOUR_ID>
api_hash = '<YOUR_HASH>'

# Here you define the target channel that you want to listen to:
user_input_channel = 'https://t.me/<CHANNEL_NAME>'
subjectFilter = ['key', 'words']
levelFilter = ['more', 'keywords']

# Not sure if 'anon' is the correct here
client = TelegramClient('anon', api_id, api_hash)

# Listen to messages from target channel 
@client.on(events.NewMessage(chats=user_input_channel)) 
async def newMessageListener(event):
    # Get message text 
    newMessage = event.message.message 

    # Apply 1st round of Regex for Subject for current messageContent — return list of keywords found (case—insensitive) 
    subjectFiltered = re.findall(r"(?=("+'|'.join(subjectFilter)+r"))", newMessage, re.IGNORECASE) 

    if len(subjectFiltered) != 0: 
        # Apply 2nd round of Regex for Level 
        levelFiltered = re.findall(r"(?=("+'|'.join(levelFilter)+r"))", newMessage, re.IGNORECASE) 

        if len(levelFiltered) != 0: 
            await client.forward_messages(entity='me', messages=event.message) 

with client: 
    client.run_until_disconnected()