title: Converting datetime with different time-zone to date in specific date
body: <p>Property to store most recent won deal stores information in rather odd format. The data is in datetime format with different timezones.</p>
  
  <p><strong>I'm getting the following errors:</strong></p>
  
  <p>"If tzaware, these values represent unix timestamps, so we" and "ValueError: Array must be all same time zone"</p>
  
  <p>When I try one of the following commands:</p>
  
  <p><code>pd.to_datetime(df1['properties__recent_deal_close_date__value']</code>)</p>
  
  <p>and</p>
  
  <pre><code>df1['properties__recent_deal_close_date__value'].dt.tz_convert('Eruope/Berlin')
  </code></pre>
  
  <p><strong>I would like to convert data such as this:</strong></p>
  
  <pre><code>2018-11-16 11:32:51.285000+01:00    
  2019-02-28 17:13:49.492000+01:00    
  2018-08-29 09:50:51+02:00   
  </code></pre>
  
  <p><strong>To this:</strong></p>
  
  <pre><code>2019-11-16
  2019-02-28
  2018-08-29
  </code></pre>