public async Task <ActionResult <CustomResponse <Guid> > > Submit(
            [FromServices] IObjectService objectService,
            [FromServices] ApplicationDbContext dbContext,
            [FromRoute][BindRequired][ModelBinder(Name = "problemsetId")] Problemset problemset,
            [FromBody] SubmitRequest request
            )
        {
            var id = await problemset.Submit(request.EntryId, request.Token);

            if (!id.HasValue)
            {
                ModelState.AddModelError("", "Invalid EntryId or Token.");
                return(BadRequest(ModelState));
            }
            return(new CustomResponse <Guid>(id.Value));
        }