You will need to sign up for a developer account. If you have difficulty manuevering through the site, I have a set of visual instructions: here
These files use the tweepy module.
pip install tweepy
You will need your own codes like these (in the Settings Tab on the developer's website) to access the API from python:

-
01_search_twitter.py
Uses the search() method.
You can find an example here: Using Python to Find Happy People Around You -
02_user_timeline_twitter.py
This also includes a csv module to save your results to a csv file.
Uses the user_timeline() method to check on another user's twitter feed. -
03_post_to_twitter.py
Uses update_status() method.
Note: Make sure to change your application status on Twitter to Read-Write, otherwise you won't be able to post to your account.