[BUG] `_distutils_hack` sometimes breaks in `virtualenv`s

setuptools version

e5156411d97a683db3365e2b778c0936b5fb620a

Python version

cpython 3.9

OS

Ubuntu 21.10 Impish

Additional environment information

Package                   Version
------------------------- -------------------
asttokens                 2.1.0
build                     0.9.0
certifi                   2022.9.24
colorama                  0.4.7.dev1
editables                 0.3
executing                 0.1.dev1+g32c2388
flit_core                 3.8.0
hatch-fancy-pypi-readme   22.8.0
hatch-vcs                 0.2.0
hatchling                 1.11.1
httpcore                  0.16.1
httpx                     0.23.1
icecream                  2.1.3
installer                 0.6.0.dev0
ipi                       0.1.dev1+g58bf835
packaging                 21.4.dev0
pathspec                  0.10.2
peval                     0.1.dev1+g2f68c8c
pip                       23.0.dev0
pluggy                    0.1.dev1+gd0c0cac
plumbum                   0.1.dev1+g4ea4a2c
Pygments                  2.13.0
pyproject_hooks           1.0.0
requests                  2.28.1
requests-file             0.1.dev1+g675c7a6
rfc3986                   2.0.0
RichConsole               0.1.dev1+g954197c
securesystemslib          0.1.dev1+gfccaee8
securesystemslib-KOLANICH 0.1.dev1+g49c432c
setuptools                65.6.2.post20221123
setuptools-scm            0.1.dev1+ga70d44b
sh                        1.14.3
sniffio                   1.3.0+dev
tomli                     2.0.1
transformerz              0.1.dev1+g607eef8
tuf                       2.0.0
tuft                      0.1.dev1+g1a99478
typing_extensions         4.4.0
wheel                     0.38.4

Description

It seems that setuptools breaks when the check sees a path from a venv. It is strange. It started happening only after installation of the bunch of packages into the venv.

Expected behavior

No assertion

How to Reproduce

I have encountered it when debugging ipi (my new package manager, replacement for pip) self-bootstrapping within a venv. I'm not sure you should try

Output

File "~/ipi.py/ipi/utils/metadataExtractor.py", line 24, in <module>
  from setuptools.config import read_configuration as parseSetupCfg
File "~/ipi.py/test_venv/lib/python3.9/site-packages/setuptools/__init__.py", line 8, in <module>
  import _distutils_hack.override  # noqa: F401
File "~/ipi.py/test_venv/lib/python3.9/site-packages/_distutils_hack/override.py", line 1, in <module>
  __import__('_distutils_hack').do_override()
File "~/ipi.py/test_venv/lib/python3.9/site-packages/_distutils_hack/__init__.py", line 77, in do_override
  ensure_local_distutils()
File "~/ipi.py/test_venv/lib/python3.9/site-packages/_distutils_hack/__init__.py", line 64, in ensure_local_distutils
  assert '_distutils' in core.__file__, core.__file__
AssertionError: /usr/lib/python3.9/distutils/core.py

Start by reproducing the traceback in a Python 3.9 virtualenv on Ubuntu, focusing on setuptools.config and the _distutils_hack override path shown in the report. Check why ensure_local_distutils sees /usr/lib/python3.9/distutils/core.py instead of the expected local module. Done means the reported import completes without the assertion in the affected virtualenv scenario.