'Maintain state of versions that are wanted.'

@decorators.detail_route()
def valid_versions(self, request, **kwargs):

    project = get_object_or_404(Project.objects.api(request.user), pk=kwargs['pk'])
    if ((not project.num_major) or (not project.num_minor) or (not project.num_point)):
        return Response({'error': 'Project    does    not    support    point    version    control'}, status=status.HTTP_400_BAD_REQUEST)
    version_strings = project.supported_versions()
    project.versions.filter(verbose_name__in=version_strings).update(active=True)
    return Response({'flat': version_strings})
