'incr/decr the \'spammer\' field for the author of every
passed thing'

def author_spammer(self, things, spam):

    by_aid = {}
    for thing in things:
        if (hasattr(thing, 'author_id') and (not getattr(thing, 'ban_info', {}).get('auto', True))):
            by_aid.setdefault(thing.author_id, []).append(thing)
    if by_aid:
        authors = Account._byID(by_aid.keys(), data=True, return_dict=True)
        for (aid, author_things) in by_aid.iteritems():
            author = authors[aid]
            author._incr('spammer', (len(author_things) if spam else (- len(author_things))))
