Python 3.13.0b3: AttributeError: 'functools.partial' object has no attribute '__name__'

[musicinmybrain]

$ gh repo clone encode/starlette
$ cd starlette
$ python3.13 --version
Python 3.13.0b3
$ python3.13 -m venv _e
$ . _e/bin/activate
(_e) $ pip install -r requirements.txt
(_e) $ pip install -e .
(_e) $ python -m pytest
_e/lib64/python3.13/site-packages/trio/_path.py:164: in generate_forwards
    raise TypeError(attr_name, type(attr))
E   TypeError: ('parser', <class 'module'>)
(_e) $ pip install --upgrade trio
(_e) $ python -m pytest
==================================================================================================== ERRORS ====================================================================================================
____________________________________________________________________________________ ERROR collecting tests/test_routing.py ____________________________________________________________________________________
tests/test_routing.py:135: in <module>
    Route("/", endpoint=functools.partial(partial_endpoint, "foo")),
starlette/routing.py:227: in __init__
    self.name = get_name(endpoint) if name is None else name
starlette/routing.py:103: in get_name
    return endpoint.__name__
E   AttributeError: 'functools.partial' object has no attribute '__name__'. Did you mean: '__ne__'?
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! Interrupted: 1 error during collection !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
=============================================================================================== 1 error in 0.64s ===============================================================================================

This appears to be a new regression in Python 3.13.0b3 (vs. 3.13.0b2).

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• Initially raised as discussion Plans for Python 3.13 support? #2610 – “Please file an issue in this repo for any incompatibility you encounter with 3.13.”

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[mgorny]

This is according to the documentation:

partial objects are like function objects in that they are callable, weak referenceable, and can have attributes. There are some important differences. For instance, the name and doc attributes are not created automatically.

https://docs.python.org/3/library/functools.html#partial-objects