title: pyplot animation example code won't animate
body: <p>I'm trying to come up to speed on the animation functionality in pyplot. I've grabbed the example code given here: <a href="https://matplotlib.org/2.0.0/examples/animation/animate_decay.html" rel="nofollow noreferrer">https://matplotlib.org/2.0.0/examples/animation/animate_decay.html</a></p>
  
  <p>and I'm attempting to run it myself. The result I get is empty axes with no animation at all. My setup is anaconda 4.3, with python 3.6. Matplotlib is version 2.0.0, and I'm running this in a jupyter notebook. I've tried IE 11, Chrome 59 and Firefox 54 on both a windows 7 machine and a Mac.</p>