[BUG] SETUPTOOLS_USE_DISTUTILS=local makes any `distutils` import very slow

setuptools version

setuptools==65.3.0

Python version

python 3.8.10

OS

ubuntu 20.04

Additional environment information

No response

Description

when using the bundled distutils, importing any part of distutils takes almost 10x longer than previously

I originally started with trying to figure out why virtualenv got way slower recently and ended up tracing it to setuptools>=60

Expected behavior

I expect the bundled distutils to not incur the import time problems of setuptools

How to Reproduce

compare the following:

• time env SETUPTOOLS_USE_DISTUTILS=local venv3/bin/python3 -c 'import distutils.version'
• time env SETUPTOOLS_USE_DISTUTILS=stdlib venv3/bin/python3 -c 'import distutils.version'

Output

$ best-of -n 10 -- env SETUPTOOLS_USE_DISTUTILS=local venv3/bin/python3 -c 'import distutils.version'
..........
best of 10: 0.254s
$ best-of -n 10 -- env SETUPTOOLS_USE_DISTUTILS=stdlib venv3/bin/python3 -c 'import distutils.version'
..........
best of 10: 0.021s

best-of here is just a script which runs the command in a loop and reports the fastest time -- time also works to reproduce this

Start by reproducing the two commands in the issue with SETUPTOOLS_USE_DISTUTILS set to local and stdlib, and confirm the import-time difference on the stated Python and Ubuntu versions. Trace the bundled distutils import path to identify where the extra work occurs. Done means the local bundled implementation no longer has the reported import-time regression, with the comparison commands or a regression test demonstrating the result.