[Forward compatibility][BUG] pkg_resources.extern.VendorImporter lacks exec_module() method (original) (raw)

This causes an ImportWarning that effectively explodes in envs with a strict warning handling (filterwarnings = error) — like pytest — under Python 3.10-dev that ships setuptools v47.1.0. But I checked that the importer is still missing that method.
The simple repro is:

$ python3.10 -W error -c 'import pkg_resources' Traceback (most recent call last): File "", line 1, in File "~/.pyenv/versions/3.10-dev/lib/python3.10/site-packages/pkg_resources/init.py", line 57, in from pkg_resources.extern import six File "", line 1026, in _find_and_load File "", line 1005, in _find_and_load_unlocked File "", line 681, in _load_unlocked ImportWarning: VendorImporter.exec_module() not found; falling back to load_module()

Example failure: https://github.com/cherrypy/cheroot/runs/1533924692?check_suite_focus=true#step:14:226.