title: "python3" is executing "python3.8" instead of "python3.9"
body: <p>I'm using Ubuntu and I just updated my python3 from 3.8 to 3.9 but when I'm running Python3 on terminal it opens the
  3.8 version and not the 3.9.
  <br>
  How can I change this? thanks a lot.<br><a href="https://i.stack.imgur.com/Gt3jx.png" rel="nofollow noreferrer">python3 --version</a></p>