title: django get record which is latest and other column value
body: <p>I have a model with some columns, between them there are 2 columns: equipment_id (a CharField) and date_saved (a DateTimeField).<br />
  I have multiple rows with the same equipment_id and but different date_saved (each time the user saves the record I save the now date time).<br />
  I want to retrieve the record that has a specific equipment_id and is the latest saved, i.e.:<br />
  | Equipment_id | Date_saved |</p>
  <p>| --- ----- | --------------------- -------- |</p>
  <p>| 1061a   | 26-DEC-2020 10:10:23|<br />
  | 1061a   | 26-DEC-2020 10:11:52|<br />
  | 1061a   | 26-DEC-2020 10:22:03|<br />
  | 1061a   | 26-DEC-2020 10:31:15|<br />
  | 1062a   | 21-DEC-2020 10:11:52|<br />
  | 1062a   | 25-DEC-2020 10:22:03|<br />
  | 1073a   | 20-DEC-2020 10:31:15|<br />
  I want to retrieve for example the latest equipment_id=1061.<br />
  I have tried various approach without success:</p>
  <pre><code>prg = Program.objects.filter(equipment_id=id)  
  program = Program.objects.latest('date_saved')
    
  </code></pre>
  <p>when I use program I get the latest record saved with no relation to the previous filter</p>