public static IEnumerable <T> FindAll <T>(this ICommandService service)
 {
     if (service == null)
     {
         throw new ArgumentNullException(nameof(service));
     }
     return(service.Find(null).Enumerate <T>());
 }
 public static T Find <T>(this ICommandService service, object identifier)
 {
     if (service == null)
     {
         throw new ArgumentNullException(nameof(service));
     }
     return(service.Find(identifier).Enumerate <T>().FirstOrDefault());
 }