public void Put(ProductBll model)
        {
            if (model.Name == null || model.Category == null)
            {
                throw new InvalidProductExeptions("The required fields are missing");
            }
            try
            {
                var product = new ProductBll()
                {
                    Id = model.Id, Category = model.Category, Name = model.Name, Price = model.Price
                };
                Products.ToList().Add(product);
            }
            catch (InvalidProductExeptions)
            {
                throw new InvalidProductExeptions("The required fields are missing");
            }

            catch (NullReferenceException ex)
            {
                throw new NullReferenceException($"Exception caught: {ex}");
            }
            catch (Exception ex)
            {
                throw new Exception($"Exception occurred: {ex}");
            }
        }
        public void Post(ProductBll model)
        {
            if (model.Name == null)
            {
                throw new InvalidProductExeptions("Unable to add product without name");
            }
            try
            {
                var product = new ProductBll()
                {
                    Id = model.Id, Category = model.Category, Name = model.Name, Price = model.Price
                };
                Products.ToList().Add(product);
            }
            catch (InvalidProductExeptions)
            {
                throw new InvalidProductExeptions("Unable to add product without name");
            }

            catch (NullReferenceException ex)
            {
                throw new NullReferenceException($"Exception caught: {ex}");
            }
            catch (Exception ex)
            {
                throw new Exception($"Exception occurred: {ex}");
            }
        }