title: Unbounded range()
body: <p>Is there an unbounded version of <code>range</code> (or <code>xrange</code> for Python 2), or is it necessary to define it manually?  For example</p>
  
  <pre><code>squares = (x*x for x in range(n))
  </code></pre>
  
  <p>can only give me a generator for the squares up to <code>(n-1)**2</code>, and I can't see any obvious way to call <code>range(infinity)</code> so that it just keeps on truckin'.</p>