title: Python brackets substring not working, why?
body: <p>I am new in python and doing some testing I found this.</p>
  
  <pre><code>&gt;item="testing315testing08634567890"
  &gt;item.index("086")
  17
  &gt;item[17:10]
  ''
  &gt;item[17:]
  '08634567890'
  </code></pre>
  
  <p>I don't understand why is not working, while with other strings it works. Note that if I do this...</p>
  
  <pre><code>&gt; item[4:10]
  'ing315'
  </code></pre>
  
  <p>Are the numbers in the middle causing troubles? Is this a bug?. Did I missing something?
  I am using Python 3.3</p>