title: Openpyxl - object has no attribute 'load_workbook'
body: <p>I'm trying to load an existing workbook using openpyxl.
  But when I'm trying to run <a href="http://packages.python.org/openpyxl/usage.html#read-an-existing-workbook" rel="noreferrer">this code</a> - I'm getting following error:</p>
  
  <pre><code>AttributeError: 'module' object has no attribute 'load_workbook'
  </code></pre>
  
  <p><code>import openpyxl</code> works fine, what I'm doing wrong?</p>