Security sanitization to silence some linters

[Dervish13]

I have updated the code a little bit, to improve security.

[jaredhendrickson13]

Thanks for contributing!

This looks fine for the most part, but the shell argument in the subprocess.call definitions should also be changed to False to support the argv style command consistently and further improve security.

[Dervish13]

Hey, I have changed shell argument to False. Would you like me to squash commits, or leave it as is?

[jaredhendrickson13]

It's fine as is. Thanks!