public void When_1YearOld_Expect_1()
{
DateTime dob = DateTime.Now.AddYears(-1).AddDays(-1);
int result = age.Calculate(dob);
Assert.Equal(1, result);
}
public async Task <Age> GetAgeObjectAsync(DateTime birth, DateTime visit)
{
Age age = new Age(birth, visit);
_ = await age.Calculate(birth, visit);
return(age);
}