title: ipython notebook is not updating when I change my code
body: <p>So, I ran into a weird issue using an ipython notebook and not sure what to do.  Normally, when I run a part of the code, if there is an error, I would trace it back, fix it, and then re-run the code. I was doing a similar thing but even after making changes to the code, it looks like nothing is changing!</p>
  
  <p>Here is the example... I am using Python 3.5 so xrange is gone.  This then caused an error to be thrown:</p>
  
  <pre><code>XXXX
       24     XXXX
       25     XXXX
  ---&gt; 26     for t in xrange(0,len(data),1):
       27 
       28         XXXX
  
       NameError: name 'xrange' is not defined
  </code></pre>
  
  <p>but after changing my code (which you can see below the difference in line 26), the same error pops up!</p>
  
  <pre><code>XXXX
       24     XXXX
       25     XXXX
  ---&gt; 26     for t in range(0,len(data),1):
       27 
       28     XXX
  
       NameError: name 'xrange' is not defined
  </code></pre>
  
  <p>Any ideas on why this would be happening?</p>