foo.py

import praw

from collections import defaultdict

reddit = praw.Reddit(user_agent='karma_scraper')
reddit.login('username', 'password')
subreddit = reddit.get_subreddit('combatfootage')
response = subreddit.get_top(limit=50)
results = defaultdict(int)

for val in response:
  author = "[deleted]" if val.author is None else val.author.name
  results[author] += val.score

for key, value in sorted(results.iteritems(), key=lambda (k,v): (v,k), reverse=True):
  print "%s: %s" % (key, value)