title: Infinity generated in python code
body: <p>I'm looking over some complex Python 2.6 code which is occasionally resulting in an infinity being generated (at least an Infinity being serialized by the json library -- which checks w/ math.isinf).</p>
  
  <p>What is especially baffling is that Python (as far as I can tell) shouldn't be able to ever produce computation results set to infinity.  Am I wrong with this assumption?  I was aware you can only get infinities from constants:</p>
  
  <pre><code>k = float('inf')
  k = 1e900
  </code></pre>