text: Title: Topic 3: Some tree schemes are not rendered
  Body: ![2018-11-06 00-10-39 jupyter notebook viewer - google chrome](https://user-images.githubusercontent.com/1929262/48027182-1e361580-e159-11e8-99c1-3673d7150172.jpg)
  
  The following cells do not render the tree scheme in the [article](https://mlcourse.ai/notebooks/blob/master/jupyter_english/topic03_decision_trees_kNN/topic3_decision_trees_kNN.ipynb): **In[9], In[13], In[24], In[32]**. Checked in Chrome and Firefox.
  
  There is a similar [closed issue](https://github.com/Yorko/mlcourse.ai/issues/376), but the problem remained.