assertMapEquals(bimap, "one", 1, "two", 2, "three", 3, "four", 4, "five", 5);
    assertMapEquals(bimap.inverse(), 1, "one", 2, "two", 3, "three", 4, "four", 5, "five");
  }

  public void testDuplicateValues() {
    ImmutableMap<String, Integer> map =
        new ImmutableMap.Builder<String, Integer>()
            .put("one", 1)
            .put("two", 2)
            .put("uno", 1)
            .put("dos", 2)