public void GetAppointmentEndTimeTest()
        {
            var validInicio = "14:00"; var validDuracao = 90;
            var expectedValid = "15:30";
            var resultValid   = CustomDateTime.GetAppointmentEndTime(validInicio, validDuracao);

            Assert.AreEqual(resultValid, expectedValid);

            var expectedNotValid = "14:30";
            var resultNotValid   = CustomDateTime.GetAppointmentEndTime(validInicio, validDuracao);

            Assert.AreNotEqual(resultNotValid, expectedNotValid);
        }