Make the README example code more portable

[SEJeff]

Also, the $HOME variable can be modified while os.path.expanduser() does the right thing.

This works on windows as well whereas the previous code did not.

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[SEJeff]

I signed it!

[SEJeff]

If this seems sensible, I can change the actual code as well.

[mbohlool]

It does make sense. Please change example codes too and let me know when it is ready for review. Thanks for your contribution.

[SEJeff]

@mbohlool all you good sir. I figured I could start small contributing to some of the k8s ecosystem projects. Maybe I'll be able to help you grow this project to graduate out of the incubator.

[sebgoa]

lgtm