public EvaluationCoachee Update(UpdateEvaluationCoacheeCommand command)
        {
            var evaluation = _repository.GetOne(command.Id);

            if (command.Evaluation > 0)
            {
                evaluation.ChangeEvaluation(command.Evaluation);
            }
            if (!string.IsNullOrEmpty(command.Observation))
            {
                evaluation.ChangeObservation(command.Observation);
            }

            _repository.Update(evaluation);

            if (Commit())
            {
                return(evaluation);
            }

            return(null);
        }