def METHOD_NAME(self, request, *args, **kwargs):
    """
    Upload attachments for a specific session/question. The attachment will be validated and stored in the
    default_storage. The original name and location of the attachment will be stored in the payload of the answer.
    """
    session_service = get_session_service_or_404(self.get_object())
    context = self.get_serializer_context(session_service=session_service)
    serializer = self.serializer_class(data=request.data, context=context)
    serializer.is_valid(raise_exception=True)
    serializer.save()
    serializer = PublicSessionSerializer(session_service.session, context=context)
    return Response(serializer.data, status=201)