title: convert a date string to datetime compatible to postgresql
body: <p>I have a date string in the format, </p>
  
  <pre><code>"dd/mm/yyyy"
  e.g="23/2/2017"
  </code></pre>
  
  <p>How can I convert this to a valid format, so that I can save this value in Datetime field of postgresql.</p>
  
  <p>I tried using datetime package, but not getting.</p>