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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def print_topics(self, Nwords=10):
 """ Print the top ``Nwords`` words for each topic. """

        print('Topic\tTop %i words' % Nwords)
        for k, words in self.list_topics(Nwords):
            print(unicode(k).ljust(3) + '\t' + ' '.join(list(zip(*words))[0]))