python - Django filter ManyToMany relationship from a single object -

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i've got object in django, , 1 of it's properties manytomany relationship. ok, i've got object, , want know if there's data related, how can it?

here's code:

u = request.user ide = request.post['id'] defob = defobjc.objects.get(id=ide) if defob.filter(student_def=u).exists():   #do things

and here's object class:

class defobjc(models.model):   name = models.charfield(max_length=100, blank=true, null=true)   date = models.datetimefield(blank=true, null=true)   student_def = models.manytomanyfield(user, related_name='defobjc_relation', blank=true, null=true)

how can that?

the result of get() model instance, not queryset, can't filter on it. instead:

if defob.student_def.filter(id=u.id).exists():     # things

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