class Set(models.Model):
    teamplayers = models.ManyToManyField('TeamPlayer')
[...]
class TeamPlayer(models.Model):
    team = models.ForeignKey(Team)
    player = models.ForeignKey(Player)
    to = models.DateField(auto_now=False, null=True)
[...]

Set.objects.filter(teamplayers=playerX).filter(teamplayers=playerY).filter(teamplayers=playerZ) ## jakie alternatywy?