python style

[danpovey]

We should probably switch to a more standard python style for the scripts.
The tool 'flake8' seems pretty good as a style checker.
E.g. you can do
pip install --user flake8
[make sure ~/.local/bin is on your path]
flake8 foo.py
and its output can be parsed by emacs in compile mode, I think it has something similar for vim.

@keli78, perhaps you could work on this? It's quite a lot of editing. Or @wantee, do you have time?

[wantee]

vim-flake8 seems to be the vim alternative.
I'm not sure about my time, maybe I can help with a portion of files.