title: using Matplotlib how to highlight one point in the final plot
body: <p>Suppose, I have <code>x = [1,2,3,4,5,6]</code> and the corresponding <code>y = [3,4,5,6,7,8]</code>.</p>
  
  <p>I want the first pair <code>(1,3)</code> to be in a different color or shape.</p>
  
  <p>How can this be done using python?</p>