public virtual ContentFragment CreateFragment(Guid contentGuid, string personalizationGroup, IEnumerable <Guid> visitorGroups)
        {
            var markupGenerator = _markupGeneratorFactory.CreateSecuredFragmentMarkupGenerator();

            markupGenerator.ContentGroup = personalizationGroup;
            markupGenerator.RoleSecurityDescriptor.RoleIdentities = visitorGroups.Select(g => g.ToString());
            return(_fragmentFactory.CreateContentFragment(null, contentGuid, markupGenerator));
        }