title: Python Pandas date_range
body: <pre><code>dateindex = pd.date_range(pd.datetime.today(), periods=4, freq='W', dtype='datetime64[ns]')
  </code></pre>
  
  <p>to generate some dates.</p>
  
  <p>Can I get something like this to generate dates in the past.  I tried -4 but no joy.</p>
  
  <p>Cheers
  Kevin</p>