title: python -- callable iterator size?
body: <p>I am looking through some text file for a certain string with the method.</p>
  
  <p><code>re.finditer(pattern,text)</code>  I would like to know when this returns nothing. meaning that it could find nothing in the passed text.</p>
  
  <p>I know that callable iterators, have <code>next()</code> and <code>__iter__</code></p>
  
  <p>I would like to know if I could get the size or find out if it returns no string matching my pattern.</p>