New GitHub issue #118895 from AlexWaygood:<br>
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<pre>
# Bug report
### Bug description:
Most sentinels in Python raise `AttributeError` if you try to assign attributes to them, but `typing.NoDefault` raises `TypeError` instead. I think this should be `AttributeError`, for consistency with other similar objects:
```pycon
(main) % ./python.exe ~/dev/cpython
Python 3.14.0a0 (heads/main:66f8bb76a1, May 8 2024, 17:00:15) [Clang 15.0.0 (clang-1500.3.9.4)] on darwin
Type "help", "copyright", "credits" or "license" for more information.
>>> None.foo = 'bar'
Traceback (most recent call last):
File "<python-input-0>", line 1, in <module>
None.foo = 'bar'
^^^^^^^^
AttributeError: 'NoneType' object has no attribute 'foo' and no __dict__ for setting new attributes
>>> NotImplemented.foo = 'bar'
Traceback (most recent call last):
File "<python-input-1>", line 1, in <module>
NotImplemented.foo = 'bar'
^^^^^^^^^^^^^^^^^^
AttributeError: 'NotImplementedType' object has no attribute 'foo' and no __dict__ for setting new attributes
>>> from typing import NoDefault
>>> NoDefault.foo = 'bar'
Traceback (most recent call last):
File "<python-input-3>", line 1, in <module>
NoDefault.foo = 'bar'
^^^^^^^^^^^^^
TypeError: 'NoDefaultType' object has no attributes (assign to .foo)
```
### CPython versions tested on:
CPython main branch
### Operating systems tested on:
macOS
</pre>
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<a href="https://github.com/python/cpython/issues/118895">View on GitHub</a>
<p>Labels: type-bug, topic-typing, 3.13, 3.14</p>
<p>Assignee: </p>