twitter challange again

main2.py

import collections

users = []


def train(filename="trainingdata.txt"):
    global users
    tweeters = {}
    first = True
    f = open(filename)
    for line in f:
        if first:
            first = False
            continue
        user, tweet = line.split(' ', 1)
        tweeters.setdefault(user, collections.Counter([]))
        c = collections.Counter(tweet.lower().split())
        tweeters[user] += c
    f.close()
    users = tweeters.keys()
    training_probabilities = {}
    totals = collections.Counter()
    for user in tweeters:
        totals += tweeters[user]
    for word in totals:
        training_probabilities[word] = dict((user, float(tweeters[user][word]+1)/float(totals[word] + len(tweeters.keys()))) for user in tweeters)
    return training_probabilities


def predict(tweet, training_probabilities):
    global users
    current_probabilities = dict((x, 1.0) for x in users)
    for word in tweet.lower().split():
        if word in training_probabilities:
            for key in current_probabilities:
                current_probabilities[key] *= training_probabilities[word][key]
    # print current_probabilities
    max_value, max_key = 0, ''
    for key in users:
        if current_probabilities[key] >= max_value:
            max_key = key
            max_value = current_probabilities[key]
    return max_key

if __name__ == '__main__':
    # probs = train()
    # print Prob()
    training_probabilities = train()
    for i in xrange(int(raw_input())):
        print predict(raw_input(), training_probabilities)