Run is the simplest way to run a command and post its execution status to slack :

Just prefix any commands with run:

run python script.py

Download the latest release to /usr/local/bin/run.

Add a run-config.json file to your $HOME/.run/run-config.json:

{
  "slack": {
    "token": "1234",
    "channel": "monitoring",
    "username": "server-01",
    "emoji": ":gear:"
  }
}