class subject_add_form(forms.Form):
    groups = []
    for i in Groups.objects.filter(group__gte = int(request.session['id'])*10, group__lte = (int(request.session['id'']+1))*10)[:]:
        groups.append((i.id, i.group))
   groups = forms.MultipleChoiceField(choices=groups, label=u'Группы')

    def __init__(self, request, *args, **kwargs):
        super(subject_add_form, self).__init__(*args, **kwargs)
        self.request = request
    def printer(self, request):
        print self.request
    printer(self.request)

groups=Groups.objects.filter(group__gte = int(request.session['id'])*10, group__lte = (int(request.session['id'']+1))*10).values_list('id','group')
form=Subject_add_form(groups)

class Subject_add_form(forms.Form):
        groups = forms.MultipleChoiceField(choices=(), label=u'Группы')
        def __init__(self, groups, *args, **kwargs):
            super(Subject_add_form, self).__init__(*args, **kwargs)
            self.fields['groups'].choices=groups