title: matplotlib: Two chart types with two axes
body: <p>I would like to make a following chart using matplotlib:</p>
  
  <p><img src="https://i.stack.imgur.com/BpxaD.png" alt="Two chart types with two axes "></p>
  
  <p>From <a href="http://matplotlib.org/examples/pylab_examples/bar_stacked.html" rel="nofollow noreferrer">this example</a> I know how to make a stacked column chart.</p>
  
  <p>How do I draw a line (with a corresponding secondary axis) on top of the columns?</p>