title: module 'xlwings' has no attribute 'Book'
body: <p>I'm trying to use xlwings for the first time but I can't quite understand the documentation.
  From the section "Quickstart"  I read </p>
  
  <pre><code>import xlwings as xw       
  
  wb = xw.Book()  # this will create a new workbook    
  </code></pre>
  
  <p>When I try this "at home", I have no problem importing xlwings but with the second script I get this error:</p>
  
  <pre><code>AttributeError: module 'xlwings' has no attribute 'Book'
  </code></pre>
  
  <p>When I try to see the attributes of xw I can see AboveBelow,ActionTime etc. but not Book.</p>
  
  <p>Can you help please?</p>
  
  <p>Thank you very much. </p>