title: Pandas - how to remove whitespace in datetime column conversion to avoid error?
body: <p>I have a dataframe with columns like below:</p>
  
  <pre><code>                  Time             Offset
  0  2019/07/15 11:47:24                NaN  
  1  2019/07/15 11:47:47             0.0001   
  2  2019/07/15 11:51:46             0.0004  
  3  2019/07/15 11:51:51             0.0003   
  4  2019/07/15 12:30:00                NaN
  </code></pre>
  
  <p>When I try to run <code>df['Time'] = pd.to_datetime(df['Time'],format='%Y/%m/%d %H:%M:%S')</code> on it, returned is <code>ValueError: time data 2019/07/15 nan doesn't match format specified</code>. Why is that <code>nan</code> present and / or how can I get rid of it to convert the column to datetime?</p>