public void CustomerManager_GetCustomersByRegion_InProcessorCacheTest()
        {
            var cache           = new InProcessorCache.Cache <IEnumerable <Customer> >();
            var customerManager = new CustomersManager(cache);

            long executionTimeWithoutCaching = 0;
            long executionTimeWithCaching    = 0;

            var region = "RJ";

            _stopwatch.Start();

            var inProcessorCacheResult1 = customerManager.GetCustomersByRegion(region);

            _stopwatch.Stop();

            executionTimeWithoutCaching = _stopwatch.ElapsedMilliseconds;

            _stopwatch.Restart();

            var inProcessorCacheResult2 = customerManager.GetCustomersByRegion(region);

            _stopwatch.Stop();

            executionTimeWithCaching = _stopwatch.ElapsedMilliseconds;

            Assert.IsTrue(executionTimeWithoutCaching > executionTimeWithCaching);
        }