Resolve variable name issues per PEP8

Resolve variable name issues per PEP8

Move all logic under `if __name__ == "__main__"` to a `main(..)`
function.

The purpose of this is to not only address flake8/pylint reported issues
with variable names, but also to enable testing of the function in
isolation to ensure the logic acts as desired.

Signed-off-by: Enji Cooper <yaneurabeya@gmail.com>