title: How do I make bar plots automatically cycle across different colors?
body: <p>In <code>matplotlib</code>, line plots color cycle automatically. These two line plots would have different colors.</p>
  
  <pre><code>axes.plot(x1, y)
  axes.plot(x2, y)
  </code></pre>
  
  <p>However, bar plots don't. Both these data series will have blue bars.</p>
  
  <pre><code>axes.bar(x1, y)
  axes.bar(x2, y)
  </code></pre>
  
  <p>How do I make bar plots cycle automatically across a predefined set of colors?</p>