Bug report

Please see the below minimal repro:

from threading import Lock, RLock

class SubclassLock(Lock):
    pass

class SubclassRLock(RLock):
    pass

The subclass of Lock emits:

Traceback (most recent call last):
  File "/path/to/file.py", line 3, in <module>
    class SubclassLock(Lock):
TypeError: cannot create 'builtin_function_or_method' instances

The subclass of RLock emits:

Traceback (most recent call last):
  File "/path/to/file.py", line 6, in <module>
    class SubclassRLock(RLock):
TypeError: function() argument 'code' must be code, not str

Both of these messages are relatively cryptic. I think if Python doesn't support subclassing Lock/RLock, it should be documented in threading, and this error message should be more friendly/clear.

Your environment

• CPython versions tested on: 3.10.3
• Operating system and architecture: macOS Big Sur 11.5.1