Ошибка AttributeError at /api/v1/applicant/applicants/
'list' object has no attribute 'id' Возникает когда в вызове ложу скобки []
Код
def send_notification(data, user, req_user, email):
    channel_layer = get_channel_layer()
    group_name = 'user_id_{0}'.format(user.id)
    print(group_name)
    for group in group_name:
        async_to_sync(channel_layer.group_send)(group,
                                                {
                                                    "type": "notify",
                                                    "text": data,
                                                },
                                                )
    if email:
        send_mail(subject='Уведомление', message=f"{data}", from_email=req_user.email,
                  recipient_list=[user.email])  # from_email-от кого и recepient_list-кому
    notify = Notification.objects.create(sender=req_user, message=data)
    notify.receivers.add(user)
    notify.save()
Вызов
 applicant1 = User.objects.all().get(username="applicant1")
            applicant2 = User.objects.all().get(username="applicant0")
            notify_text = 'SomeMessageforGroup'
            send_notification(notify_text, user=[applicant1, applicant2], req_user=user_id,
                              email=False)