title: django query all with filtering on the related set?
body: <pre><code>class Customer(models.Model):
    name = models.CharField(max_length=200)
    # ..
  
  
  class CustomerTicket(models.Model):
    customer = models.OneToOneField(Customer)
    date = models.DateTimeField(auto_now_add=True)
    # ..
  </code></pre>
  
  <p>I want to query <strong>all</strong> customers. And, adding for each customer its ticket if it has one in the date range - so I will get the ticket object only if it is in the given date range, otherwise the ticket field would be null.</p>