title: Add extra button to django model admin page
body: <p>This is what my admin page for 1 of my models currently look like:</p>
  
  <p><img src="https://i.imgur.com/79yvGpx.png" alt="Screenshot"></p>
  
  <p>I would like to add a button next to the <code>Add note</code> button which will allow me to perform a django action. Is there a way I can get this done? I just want the button to scan the notes and delete the empty ones, but that part I can work out. I just want to know how I can add a button next to <code>Add note</code> so I can link this to django.</p>
  
  <p>Thank you for your help!</p>