protected override void Setup()
        {
            _adminClient = new PostmarkAdminClient(WRITE_ACCOUNT_TOKEN);
            var id = Guid.NewGuid();

            _senderprefix   = "test-sender-";
            _returnPath     = "test." + WRITE_TEST_SENDER_SIGNATURE_PROTOTYPE.Split('@')[1];
            _senderEmail    = WRITE_TEST_SENDER_SIGNATURE_PROTOTYPE.Replace("[TOKEN]", String.Format(_senderprefix + "{0:n}", id));
            _replyToAddress = WRITE_TEST_SENDER_SIGNATURE_PROTOTYPE.Replace("[TOKEN]", String.Format(_senderprefix + "replyto-{0:n}", id));
            _senderName     = String.Format("Test Sender {0}", TESTING_DATE);
        }
        protected override async Task SetupAsync()
        {
            _adminClient = new PostmarkAdminClient(WRITE_ACCOUNT_TOKEN);
            var id        = Guid.NewGuid();
            var baseEmail =
                _senderprefix = "test-sender-";

            _senderEmail    = WRITE_TEST_SENDER_SIGNATURE_PROTOTYPE.Replace("[token]", String.Format(_senderprefix + "{0:n}", id));
            _replyToAddress = WRITE_TEST_SENDER_SIGNATURE_PROTOTYPE.Replace("[token]", String.Format(_senderprefix + "replyto-{0:n}@example.com", id));
            _senderName     = String.Format("Test Sender {0}", TESTING_DATE);
            await CompletionSource;
        }