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Question

import sysimport json# subroutine for calculating setiment scores for each tweetsdef compute_score(text,scores):    total = 0.0    words = text.split()    for word in words:        if word in scores.keys():            total = total + scores[word]    return totaldef main():    sent_file = open(sys.argv[1]) # first argument of the function call is the sentiment file    tweet_file = open(sys.argv[2]) # second argument of the function call is the tweets file    # creating a dictionary for sentiment-word mapping    scores = {} # initialize an empty dictionary to store sentiment scores for words    for line in sent_file:        term, score  = line.split("\t")  # The file is tab-delimited. "\t" means "tab character"        scores[term] = int(score)  # Convert the score to an integer.    # creating a dictionary for tweet-sentiment_score mapping    tweets_scores = {} # initialize an empty dictionary    index = 0    for line in tweet_file:        index = index + 1        tweet = json.loads(line)        text = tweet.get("text")        # calculating setiment score        if text:            text = text.encode("utf-8")            tweets_scores[index] = compute_score(text,scores)        else: tweets_scores[index] = 0.0    # print out results    for i in tweets_scores:        print(str(tweets_scores[i]))if __name__ == '__main__':    main()