BigARTM - невозможно вывести список ключевых слов по темам (Topic)

import artm
batch_vectorizer = artm.BatchVectorizer(data_path="all news.txt", data_format="vowpal_wabbit", target_folder="habrhabr", 
                                       batch_size=100)
batch_vectorizer = artm.BatchVectorizer(data_path='habrhabr',data_format='batches')
T = 6   # количество тем
model_artm = artm.ARTM(num_topics=T, topic_names=["sbj"+str(i) for i in range(T)], class_ids={"text":1})
# число после названия модальностей - это их веса
batch_vectorizer = artm.BatchVectorizer(data_path='habrhabr',data_format='batches')
dictionary = artm.Dictionary(data_path='habrhabr')# загрузка данных в словарь
model = artm.ARTM(num_topics=6,
                  topic_names=["topic_"+str(i) for i in range(T)],
                  num_document_passes=10,#10 проходов по документу
                  dictionary=dictionary,
                  scores=[artm.TopTokensScore(name='top_tokens_score')])
model.fit_offline(batch_vectorizer=batch_vectorizer, num_collection_passes=10)#10 проходов по коллекции
top_tokens = model.score_tracker['top_tokens_score']
model=model.transform(batch_vectorizer=batch_vectorizer, theta_matrix_type= 'dense_theta', predict_class_id=None )
print(model)
for topic_name in model.topic_names:
    print (topic_name)
    for (token, weight) in zip(top_tokens.last_tokens[topic_name],
                               top_tokens.last_weights[topic_name]):    
         print (token, '-', round(weight,3))

print(model)