Please provide test code for DNS Flag Day 2020 (edns512tcp)

My understanding from the DNS flag day page is that the edns512tcp test is the relevant thing to look for in terms of testing compatibility with the dns flag day 2020 requirements.

However that test seems to be unpublished. While the EDNS Compliance Tester page links to this source repo, the code does not contain the edns512tcp test.

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