Files doesn't show .py files.

[placid furnace]

They show for me, What drive type (local, network, cloud etc.) are you seeing this issue on?
What version of Files are you on. Files settings > About

So your browsing this from a network drive?

Yes it would be. It's a known issue https://github.com/files-community/Files/issues/12626. You can check there or click subscribe in the right sidebar for updates. Right now there is no timeline on when it will be fixed.