public async Task AddShow(Guid cinemaId, Guid showId, CreateShowRequest request)
        {
            Cinema cinema = await _ctx.Cinemas.Include(c => c.Shows).FirstOrDefaultAsync(c => c.Id == cinemaId);

            Movie movie = await _ctx.Movies.FindAsync(request.MovieId);

            Dictionary <Ticket, decimal> priceList = request.PriceList.ToDictionary(x => x.Kind, x => x.Price);
            Show show = ShowFactory.Create(showId, cinema, movie, request.Date, priceList);

            cinema.AddShow(show);
            await _ctx.SaveChangesAsync();
        }