switching to python3

[Larz60+]

for paths, I've been using pathlib, which created pure objects.
It still has a few quirks, but I expect they will be worked out by the next python release.
Here's some examples pay particular attention to the open statement:

>>> from pathlib import Path
>>> homepath = Path('.')
>>> print(homepath.resolve())
X:\python\m-p\m\MakerProject\venv\src
>>>
>>> datapath = homepath / 'data'
>>> print([file for file in datapath.iterdir()])
[WindowsPath('data/html'), WindowsPath('data/json'), WindowsPath('data/temp')]
>>> jsonpath = datapath / 'json'
>>> print([file for file in jsonpath.iterdir()])
[WindowsPath('data/json/images.json'), WindowsPath('data/json/images.txt'), WindowsPath('data/json/MakeText.bat'), WindowsPath('data/json/rfc_index.json'), WindowsPath('data/json/rfc_index.txt')]
>>> mktxt = jsonpath / 'MakeText.bat'
>>> with mktxt.open() as f:
...     for line in f:
...          print(f)
...
<_io.TextIOWrapper name='data\\json\\MakeText.bat' mode='r' encoding='cp1252'>
<_io.TextIOWrapper name='data\\json\\MakeText.bat' mode='r' encoding='cp1252'>
>>>