def METHOD_NAME(self):
    m = ConcreteModel()
    m.i = IntervalVar(length=2, end=(4, 9), optional=False)
    self.assertEqual(value(m.i.is_present), True)
    self.assertTrue(m.i.is_present.fixed)
    self.assertFalse(m.i.optional)
    # Should also be true by default
    m.i2 = IntervalVar()
    self.assertEqual(value(m.i2.is_present), True)
    self.assertTrue(m.i.is_present.fixed)
    self.assertFalse(m.i2.optional)