public async Task <IList <ProductByManufacturersStatisticsDto> > Handle(GetProductsStatisticsByManufacturers request, CancellationToken cancellationToken)
        {
            var notifications = GetQuery();

            var groupedTypes = await notifications
                               .GroupBy(g => new
            {
                g.ManufacturerId
            })
                               .Select(s => new
            {
                s.Key.ManufacturerId,
                Count = s.Count()
            }).ToListAsync(cancellationToken);

            var products = groupedTypes.Select(x => new ProductByManufacturersStatisticsDto
            {
                ManufacturerName = _context.Manufacturers.FirstOrDefault(y => y.Id.Equals(x.ManufacturerId))?.Name ??
                                   "deleted",
                Count = x.Count
            }).ToList();

            return(products);
        }
        public async Task <IActionResult> GetProductStatisticsByManufacturer([FromQuery] GetProductsStatisticsByManufacturers query)
        {
            var statistics = await _mediator.Send(query);

            return(Ok(statistics));
        }