Django filter the model on ManyToMany count?

Question

Suppose I have something like this in my models.py:

class Hipster(models.Model):
  name = CharField(max_length=50)

class Party(models.Model):
  organiser =          


        

Answer 1

Party.objects.filter(organizer=user, participants__isnull=False)
Party.objects.filter(organizer=user, participants=None)