I'm trying to set up a proxy model in django admin. It will represent a subset of the original model. The code from models.py:

class MyManager(models.Manager):
    def get_query_set(self):
        return super(MyManager, self).get_query_set().filter(some_column='value')

class MyModel(OrigModel):
    objects = MyManager()
    class Meta:
        proxy = True

Now instead of filter() I need to use a complex SELECT statement with JOINS. What's the proper way to inject it wholly to the custom manager?