title: How to set datatime column?
body: <p>I have some datatime columns on my dataframe. One of them appear with the object type and the other appear as datatype. How to pass tho object type one as datatype also ?</p>
  <p><a href="https://i.stack.imgur.com/bitT9.png" rel="nofollow noreferrer">enter image description here</a></p>
  <p><a href="https://i.stack.imgur.com/ftEww.png" rel="nofollow noreferrer">enter image description here</a></p>
  <p>Thank you in advance !</p>