title: Hot to add a range dashed box on a bar plot using matplotlib?
body: <p>I've made a bar chart using Birt, but due to a change of technology, I have to use Matplotlib now. I want to know if it is possible (and how) to make a similar chart using Matplotlib, especially the range dashed square around the top 80% of the bars as in example: </p>
  
  <p><img src="https://i.stack.imgur.com/7YdtC.png" alt="birt chart">. </p>
  
  <p>I didn't find any documentation on how to make it.</p>
  
  <p>Does anybody know how to proceed?</p>