You can make it easy to deal with text file without lying to your API users. open("foo", mode="t") could become open("foo").as_text(). Besides, Python has path

You can make it easy to deal with text file without lying to your API users. open("foo", mode="t") could become open("foo").as_text(). Besides, Python has pathlib now, which allows you to do Path("foo").read_text() for quick and dirty text handling already.