gistfile1.py

#!/bin/python

import praw
import sys


# recursivly parse comments and MoreComments objects

def parse_comments(comments):
    for comment in comments:
        if isinstance(comment, praw.objects.MoreComments):
            parse_comments(comment.comments())
        elif comment.is_root and comment.author is not None:
            CONTESTANTS.add(str(comment.author))

# make sure a submission id is given

if len(sys.argv) != 2:
    print("usage: {} <submission_id>".format(sys.argv[0]))
    sys.exit(1)


# create praw object and get submission contents if we have a valid id

r = praw.Reddit("local ecr giveaway extractor for fun by /u/kylebaked")

parameters = {
    "submission_id": sys.argv[1],
    "comment_limit": None,
    "comment_sort": "old",
    "params": {"depth": 1}
}

try:
    submission = r.get_submission(**parameters)
except:
    print("invalid submission id")
    sys.exit(1)

CONTESTANTS = set()
parse_comments(submission.comments)

print(CONTESTANTS)

sys.exit(1)