text: Title: mallet falls asleep
  Body: i'm using mallet-2.0.8 with Python 3 and Jupyter Notebook. Recently it worked just fine. But now it falls asleep while showing it's still working even with a small dataset. 
  The problem is with following function:
  def compute_coherence_values(dictionary, corpus, texts, limit, start=2, step=1):
      """
      Compute c_v coherence for various number of topics
      Parameters:
      ----------
      dictionary : Gensim dictionary
      corpus : Gensim corpus
      texts : List of input texts
      limit : Max num of topics
      Returns:
      -------
      model_list : List of LDA topic models
      coherence_values : Coherence values corresponding to the LDA model with respective number of topics
      """
      coherence_values = []
      model_list = []
      for num_topics in range(start, limit, step):
          model = gensim.models.wrappers.LdaMallet(mallet_path, corpus=corpus, num_topics=num_topics, id2word=id2word)
          model_list.append(model)
          coherencemodel = CoherenceModel(model=model, texts=texts, dictionary=dictionary, coherence='c_v')
          coherence_values.append(coherencemodel.get_coherence())
      return model_list, coherence_values