public void Expires_UseAddMethod_AddedValueCanBeRetrievedUsingProperty()
{
_headers.TryAddWithoutValidation("Expires", " Sun, 06 Nov 1994 08:49:37 GMT ");
Assert.Equal(new DateTimeOffset(1994, 11, 6, 8, 49, 37, TimeSpan.Zero), _headers.Expires);
_headers.Clear();
_headers.TryAddWithoutValidation("Expires", "Sun, 06 Nov 1994 08:49:37 GMT");
Assert.Equal(new DateTimeOffset(1994, 11, 6, 8, 49, 37, TimeSpan.Zero), _headers.Expires);
}