Integrating tidy in Emacs?

Hi!

What is your favorite way of integrating tidy into Emacs?
It would be great to call a function to replace the contents of the current
buffer with the tidy output.

I'm surely not the first one who wants to do this. So I thought I'll ask
here before I sit down and write some Elisp code.

I had a look at the mailing list archives, some appropriate FAQs, and Deja,
but until now I didn't find a solution.

Best Regards / Mit freundlichem Gruss
Martin Schweikert
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