public IHttpActionResult Update(int id, HomeworkRequestModel homework)
        {
            if (!this.ModelState.IsValid)
            {
                return BadRequest(this.ModelState);
            }

            var homeworkInDb = this.data.Homeworks
                .All()
                .FirstOrDefault(c => c.Id == id);

            homeworkInDb.FileUrl = homework.FileUrl;

            this.data.Homeworks.SaveChanges();

            return Ok(homeworkInDb);
        }
        public IHttpActionResult Create(HomeworkRequestModel homework)
        {
            if (!this.ModelState.IsValid)
            {
                return BadRequest(this.ModelState);
            }

            this.data
                .Homeworks
                .Add(new Homework
                {
                    FileUrl = homework.FileUrl,
                    // StudentIdentification = homework.StudentIdentification,
                    // CourseId = homework.CourseId
                });

            this.data.Homeworks.SaveChanges();

            return Ok(homework);
        }