public static ICollection <Training> Authorization(string login, string password)
        {
            UserResponce trainer = _dataProvider.Auth(login, password);

            if (trainer == null)
            {
                throw new Exception("Неправильный логин или пароль");
            }

            if (trainer.role == "trainer" || trainer.role == "admin")
            {
                List <Training> trainings = new List <Training>();

                var trainingResponeses = _dataProvider.GetTrainings(trainer.id);

                foreach (var training in trainingResponeses)
                {
                    trainings.Add(new Training(training.groupId, new User {
                        Id = trainer.id
                    }, training.trainingDate, training.trainingType));
                }

                return(trainings);
            }
            else
            {
                throw new Exception("Вы не являетесь тренером");
            }
        }