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In the following programs, we call check_reentrant_insertion("s") twice, after multiple of update and clear of dict, the Python interpreter crashes.
+++++++++++++++++++++++++++++++++++++++++++
def check_reentrant_insertion(mutate):
 class Mutating:
 def __del__(self):
 mutate(d)
 d = {k: Mutating() for k in 'abcdefghijklmnopqr'}
 for k in list(d):
 d[k] = k
def test_reentrant_insertion():
 check_reentrant_insertion("s")
 def mutate(d):
 d.update(DictTest.__dict__)
 d.clear()
 check_reentrant_insertion(test_reentrant_insertion())
test_reentrant_insertion()
+++++++++++++++++++++++++++++++++++++++++
System Info: Ubuntu 16.04
Python Version: Python 3.9.1

I can confirm this crashes.

Is this the crash you are reporting?
```
Exception ignored in: <function check_reentrant_insertion.<locals>.Mutating.__del__ at 0x100d35af0>
Traceback (most recent call last):
 File "/Users/methane/work/python/cpython/PC/xxx.py", line 5, in __del__
 mutate(d)
TypeError: 'str' object is not callable
Exception ignored in: <function check_reentrant_insertion.<locals>.Mutating.__del__ at 0x100d35c10>
Traceback (most recent call last):
 File "/Users/methane/work/python/cpython/PC/xxx.py", line 5, in __del__
Fatal Python error: _Py_CheckRecursiveCall: Cannot recover from stack overflow.
Python runtime state: initialized
Current thread 0x000000010072bd40 (most recent call first):
 File "/Users/methane/work/python/cpython/xxx.py", line 9 in check_reentrant_insertion
 File "/Users/methane/work/python/cpython/xxx.py", line 13 in test_reentrant_insertion
 File "/Users/methane/work/python/cpython/xxx.py", line 18 in test_reentrant_insertion
...
```

Like the code in #43185, #43186, #43187, this works better in 3.10.0a5, so I suspect it is another duplicate.