Thank You after Poor Interview Performance?

I had an interview 2 days ago with a hedge fund. They had given me an assignment to do and then present it. The assignment was to ingest some data, design and database, analyze the data, and build an API to return specific info about the data. I spent 6 hours on the assignment and they told me to spend no more than 8. I did a poor job on it since I didn't I haven't used some of the stack (i.e. Flask) in a while. I'd estimate that to do a job I could be proud of, I would have had to spend ~25 hours on the assignment.

Since I didn't do particularly well on the assignment, I'm wondering if I should go ahead and thank everyone and tell them I'm looking forward to hearing from them.

Basically, should I contact the HR person and say the exact same things I would have said if I thought I had done a great job?

Thanks,