title: Django model history by date and datetime
body: <p>Assume I have model like this:</p>
  
  <pre><code>class Account(models.Model):
      balance = models.IntegerField()
      debt = models.IntegerField()
      history = HistoricalRecords()
  </code></pre>
  
  <p>I'm using django-simple-history to get instance of the model as it would have existed at the provided date and time:</p>
  
  <pre><code>inst = Account.history.as_of(datetime.datetime.now().date)
  </code></pre>
  
  <p>It's working fine, but I want to get instance where balance field is represented as it would have existed at the provided date and time, and then debt field will be most recent of that date. I don't know if this is possible, didn't find anything about that.</p>