public static ActivityStream Create(ActivityAction action, string targetType, ulong targetId = 0)
{
ActivityStream activityStream = new ActivityStream();
activityStream.target_type = targetType;
activityStream.target_id = (uint)targetId;
activityStream.subject_id = action.subject_id;
activityStream.subject_type = action.subject_type;
activityStream.object_id = action.object_id;
activityStream.object_type = action.object_type;
activityStream.type = action.type;
activityStream.action_id = action.action_id;
return(activityStream);
}