slack_client.py

# ! pip install slackclient

# get your token: https://api.slack.com/custom-integrations/legacy-tokens

# composing messages: https://api.slack.com/messaging/composing

import os
from slack import WebClient
sc = WebClient(token='<your_token>', run_async=True)
sc.chat_postMessage(channel='#tasks-notifications', text='', icon_emoji=':smile:', username='') # username is the "sender" name

async def post_my_message(channel, msg):
    await sc.chat_postMessage(channel=channel, text=msg)