public IEnumerable <TeacherDto> Execute(TeacherSearchQuery request)
        {
            var getTeachers = _context.Teachers.AsQueryable();

            if (request.Keyword != null)
            {
                getTeachers = getTeachers.Where(t => t.TFirstName
                                                .ToLower()
                                                .Contains(request.Keyword.ToLower()));
            }

            if (request.OnlyActive.HasValue)
            {
                getTeachers = getTeachers.Where(std => std.IsDeleted != request.OnlyActive);
            }

            return(getTeachers
                   .Include(t => t.Courses)
                   .Select(t => new TeacherDto
            {
                Id = t.Id,
                TFirstName = t.TFirstName,
                TLastName = t.TLastName,
                Description = t.Description,
                Nationality = t.Nationality,
                CourseName = t.Courses.Select(c => c.CourseName)
            }));
        }
        public ActionResult <IEnumerable <TeacherDto> > Get([FromQuery] TeacherSearchQuery search)
        {
            var resultTeachers = _getCommandTeachers.Execute(search);

            return(Ok(resultTeachers)); //200
        }