naivebayes - News classification in Python using Multinomial NB -


i new programming in python , need write algorithm news classification (sports, culture, entertainment, world news) using multinomial nb. wrote train_data , read_data, can't seem find need in between.

from sklearn.feature_extraction.text import countvectorizer sklearn.feature_extraction.text import tfidftransformer sklearn import svm sklearn.naive_bayes import multinomialnb   def read_data(f_name):  data = [] labels = []  line in open(f_name):     if line[:6] == "title":         continue     elif line[:5] == "article":         data.append(line.strip()[7:])     elif line[:5] == "class":         klasa = line.strip()[7:]         if klasa == "sports":             labels.append(0)         elif klasa == "culture":             labels.append(1)         elif klasa == "world news":             labels.append(2)         elif klasa == "entertainment":             labels.append(3)   return data, labels  def train_model():     vectorizer = countvectorizer()     brb = getdata('data.txt')     xtrain = vectorizer.fit_transform(articles, class)``     brb1 = getdata('data_test.txt')     xtest = vectorizer.transform(articles)     nb = multinomialnb(alpha=1).fit(xtrain, class)     output = open("hw3_ans_217_2012.txt", "w")     ytest = nb.predict(xtest)