### Question:
Stack implements com.iabtcf.extras.gvl.Stack { @Override public int getId() { return id; }  @Override int getId(); @Override List<Integer> getSpecialFeatures(); @Override List<Integer> getPurposes(); @Override String getName(); @Override String getDescription();  }### Answer:
@Test public void testGetId() { Assert.assertEquals(20, stackTwenty.getId()); }