Voting bot that removes posts if threshold is not met

bot.py

import praw
from datetime import datetime


class Bot:

    REDDIT        = praw.Reddit(username='REDDIT_USERNAME',
                                password='REDDIT_PASSWORD',
                                client_id='REDDIT_CLIENT_ID',
                                client_secret='REDDIT_CLIENT_SECRET',
                                user_agent='REDDIT_USER_AGENT')
    SUBREDDIT     = 'TrueUnpopularOpinion'
    THRESHOLD_PCT = 60
    TIME_LIMIT    = {"days": 0,
                    "hours": 6,
                    "minutes": 0,
                    "seconds": 0}
    REMOVAL_MSG   = 'This post has been removed due to community votes after 6 hours.'
    TRACKED_POSTS = [] # No need to edit this, it is built by the bot as it's needed

    def run(self):
        self.AGE_CUTOFF = self.build_age_cutoff()

        self.append_new_submissions()
        self.check_tracked_submissions()

    def append_new_submissions(self):
        for submission in self.REDDIT.subreddit(self.SUBREDDIT).stream.submissions.new():
            if submission.created_utc < self.AGE_CUTOFF:
                break

            if submission.id not in [submission.id for submission in self.TRACKED_POSTS]:
                self.TRACKED_POSTS.append(submission)

    def check_tracked_submissions(self):
        untracked_submissions = []

        for submission in self.TRACKED_POSTS:
            if submission.created_utc > AGE_CUTOFF:
                continue

            untracked_submissions.append(submission.id)
            upvotes, downvotes = self.count_votes(submission)

            ratio = self.guarded_ratio(upvotes, downvotes)

            if ratio < float(self.THRESHOLD_PCT) / 100:
                submission.remove(mod_note=self.REMOVAL_MSG)

        self.cull_untracked(untracked_submissions)

    def cull_untracked(self, untracked_submissions):
        self.TRACKED_POSTS = [submission for submission in self.TRACKED_POSTS if submission.id not in untracked_submissions]

    def count_votes(self, submission):
        submission.comments.replace_more(limit=None)
        votes = (0, 0)
        for top_level_comment in submission.comments
            if top_level_comment.body.lower() == 'yes':
                votes[0] += 1
            elif top_level_comment.body.lower() == 'no':
                votes[1] += 1

        return votes

    def build_age_cutoff(self):
        days    = self.TIME_LIMIT['days'] * 86400
        hours   = self.TIME_LIMIT['hours'] * 3600
        minutes = self.TIME_LIMIT['minutes'] * 60
        seconds = self.TIME_LIMIT['seconds']

        return days + hours + minutes + seconds

    def guarded_ratio(self, up, down):
        try:
            return float(up) / float(up + down)
        except ZeroDivisionError:
            return 1.0

if __name__ == '__main__':
    bot = Bot()

    while True:
        bot.run()