@Override
  public SelJodaDateTimeZone field(SelString field) {
    String fieldName = field.getInternalVal();
    if ("UTC".equals(fieldName)) {
      return new SelJodaDateTimeZone(DateTimeZone.UTC);
    }
    throw new UnsupportedOperationException(type() + " DO NOT support accessing field: " + field);
  }
@Test
  public void testField() {
    SelType res = one.field(SelString.of("UTC"));
    assertEquals("DATETIME_ZONE: UTC", res.type() + ": " + res);
  }