public virtual Task <Person> GetPersonAsync(string personGroupId, Guid personId)
 {
     return(PolicyService.ExecuteRetryAndCapture400Errors(
                "FaceService.GetPersonAsync",
                ApiKeys.FaceRetryInSeconds,
                () =>
     {
         var result = FaceRepository.GetPersonAsync(personGroupId, personId);
         return result;
     },
                null));
 }