Remove (and backup) non-mutuals on Twitter.

remove_non_mutuals.py

#!/usr/bin/env python3

import csv
import time
import tweepy
import datetime

# Read http://docs.tweepy.org/en/v3.5.0/auth_tutorial.html to fill in the two lines below.
auth = tweepy.OAuthHandler('XXX', 'YYY')
auth.set_access_token('123', '456')

api = tweepy.API(auth, wait_on_rate_limit=True)

# Create this directory to save the people that will be removed, in case you need them back.
backup_directory = './backup/'

# Who you follow = followed.
followed = set(api.friends_ids())

# Who follows you = followers.
followers = set(api.followers_ids())

# Give the backups a unique name.
timestamp = datetime.datetime.fromtimestamp(time.time()).strftime('%Y-%m-%d-%H-%M-%S')

# Save both your followers and who you follow.
with open(backup_directory + 'followed_' + timestamp + '.csv', 'w') as myfile:
    wr = csv.writer(myfile)
    wr.writerow(followed)
with open(backup_directory + 'followers_' + timestamp + '.csv', 'w') as myfile:
    wr = csv.writer(myfile)
    wr.writerow(followers)

# Now find who your mutuals are (people you follow and who follow you).
mutuals = followers.intersection(followed)

# Who is left are the non-mutuals.
non_mutuals = followed - mutuals

# So get rid of them!
for non_mutual in non_mutuals:
    api.destroy_friendship(non_mutual)
    print(api.get_user(non_mutual).name)