title: How to convert "day, hh:mm:ss" format to hh:mm in odoo v10
body: <p>I am beginner in odoo.</p>
  <p>I want to calculate of two datetimes, my code as below</p>
  <pre><code>d1 = datetime.strptime(&quot;2021-07-12 03:24:08&quot;, &quot;%Y-%m-%d %H:%M:%S&quot;)
  d2 = datetime.strptime(&quot;2021-07-10 08:35:26&quot;, &quot;%Y-%m-%d %H:%M:%S&quot;)
  
  x = d1-d2
  </code></pre>
  <p>the result is <strong>1 day, 18:48:42</strong></p>
  <p>but i need the result with format <strong>hour:minute (hh:mm)</strong>, how to convert the 1st result into hh:mm?</p>
  <p>I appreciate your advice, thank you.</p>