def get_version(self, obj):
    if obj.version:
        path = reverse('project_version_detail', kwargs={'project_slug': obj.project.slug, 'version_slug': obj.version.slug})
        return self._absolute_url(path)
    return None
def get_version(self, obj):
    if obj.version:
        path = reverse('project_version_detail', kwargs={'project_slug': obj.project.slug, 'version_slug': obj.version.slug})
        return self._absolute_url(path)
    return None