slack is a Python package that provides an interface to Slack listed officially on slack.com.

Install via pip

$ pip install pyslack

Install from source:

$ git clone git://github.com/kn/slack.git
$ cd slack
$ python setup.py install

You need to get your Slack token from api.slack.com.

import slack
import slack.chat
slack.api_token = 'your_token'
slack.chat.post_message('#eng', 'Hello slackers!', username='mybot')

import slack.users
slack.users.list()

All methods in a preview release of Slack API are available.