The dichtomy is false. Write good 2.x code and you will only miss a few very specific (like nonlocal) or recent features. You get the benefit of using all the e

The dichtomy is false. Write good 2.x code and you will only miss a few very specific (like nonlocal) or recent features. You get the benefit of using all the existing 2.x libraries. Run 2to3 on your codebase and run your unit test suite, and see what happens. That way, once your dependencies are ported, you can be fairly sure that porting your library will be a walk in the park.