python - django, how to Use Count in Q -

i have following models:

class group(models.model):      group_name = models.charfield(max_length=16)  class member(models.model):      group = models.foreignkey('group')     member_name = models.charfield(max_length=16)     gender = models.booleanfield() #false "female", true "male" 

how can find group has no member, or number of male members zero?

i tried following, didn't work:

group.objects.filter( q(member__isnull=true) |                       q(member__isnull=false) &                       q( count(member__gender=true)=0 ) ) 

solution,

group.objects.filter(q(member__isnull=true) | ~q(member__gender=true)) 

when you're trying fetch might return multiple results, should use filter , not get

if want count query set, can use,

group.objects.filter(q(member__gender=false )).count()