Unfortunately there's no way in knowing whether a Python 2 string (str, not unicode) originating from the module should be interpreted as a bytes string or text

Unfortunately there's no way in knowing whether a Python 2 string (str, not unicode) originating from the module should be interpreted as a bytes string or text string. Python 2 doesn't have the clean separation between bytes and strings. Solutions might include adding some sort of hinting to specify the conversion, or add a Python2-like string class to Python 3, which would pollute its purity.