title: Import error: No module name sklearn.external.six
body: <p>I am currently using anaconda 4.8.3 and want to display a figure of decision tree and i have install graphviz and pydotplus library in anaconda instead of this i am getting error 'ModuleNotFoundError: No module named 'sklearn.externals.six' .this is my code:</p>
  <pre><code>from sklearn.tree import DecisionTreeClassifier
  from IPython.display import Image  
  from sklearn.externals.six import StringIO  
  from sklearn.tree import export_graphviz
  import pydot 
  features = list(df.columns[1:])
  features
  </code></pre>
  <p>This is my error:</p>
  <pre><code>ModuleNotFoundError   Traceback (most recent call last)
  &lt;ipython-input-19-0b3416ce7fda&gt; in &lt;module&gt;
  
          1 from IPython.display import Image
  ---&gt;    2 from sklearn.externals.six import StringIO
          3 from sklearn.tree import export_graphviz
          4 import pydot
          5 ModuleNotFoundError: No module named 'sklearn.externals.six'
  </code></pre>