How to change column names from numbers to names : <p>I have a dataframe which looks like this:</p>

<p><a href="https://i.stack.imgur.com/5Arqi.jpg" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/5Arqi.jpg" alt="dataframe"></a></p>

<p>I want to change the columnnames, for example: "2018-12-31 00:00:00" to "year_2018".
How can I do that?</p>
