private final transient ClassSanityTester tester;

    SerializableDummyProxy(ClassSanityTester tester) {
      this.tester = tester;
    }

    @Override
    <R> R dummyReturnValue(TypeToken<R> returnType) {
      return tester.getDummyValue(returnType);
    }

    @Override
    public boolean equals(@Nullable Object obj) {
      return obj instanceof SerializableDummyProxy;
    }