@Test
public void testAddRequiredIsa() {

  System.out.println("addRequiredIsa");
  CycObject isa = PERSON;
  NLFormat instance = NLFormat.getInstance(cyc);
  instance.addRequiredIsa(isa);
  assertEquals(1, instance.getRequiredIsas().size());
  assertTrue(instance.getRequiredIsas().contains(isa));
}