title: matplotlib error - no module named tkinter
body: <p>I tried to use the matplotlib package via Pycharm IDE on windows 10.
  when I run this code:</p>
  
  <pre><code>from matplotlib import pyplot
  </code></pre>
  
  <p>I get the following error:</p>
  
  <pre><code>ImportError: No module named 'tkinter'
  </code></pre>
  
  <p>I know that in python 2.x it was called Tkinter, but that is not the problem - I just installed a brand new python 3.5.1.</p>
  
  <p>EDIT: in addition, I also tried to import 'tkinter' and 'Tkinter' - neither of these worked (both returned the error message I mentioned).</p>