Updated shebang recommendation for python files

[ryanrichholt]

This was fixed in #149 but it looks like the change got lost somehow when the switching from the .html to .md file

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[ryanrichholt]

I signed it!

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[vapier]

commit 5120fd6b14e3135745668dc8eeb1c5581d3f4d9b (Dec 2020) included this fix