Self-referencing tuple in python

Question

Goal: create a self-referencing tuple satisfying x == (x,) in any version of Python. Standard libraries, matplotlib, numpy, pandas only.

Answers meeting this extra condition are prioritised (which may be impossible): this tuple should also be insertable into a dict or set.

If the extra condition is impossible, apart from the low-hanging optimization of the below code, I am still interested in a qualitatively different approach of similar length or better.

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I had previously assumed this answer to be one of the shortest, but as @mousetail brought up, actually it crashes python when inserted into a dict or set.

import ctypes
tup = (0,)
ctypes.c_longlong.from_address(id(tup)+24).value = id(tup)

I notice this also happens with the other answer in that post, so I'm wondering if there's a way to resolve it (the ideal answer), or if that is inherent in python.

Answer 1

Python 3, 48 bytes

from marshal import*
t=loads(b'\xa9\1r\0\0\0\0')

Try it online!

Not portable, depends on the interpreter. There's probably a similar (portable) pickle version, although it would need to be handcrafted since the pickle.dumps gives an error due to recursion depth.

Uses marshal, which is a standard library for serializing Python objects. The string is the string received by serializing the object produced by the code in the question.