Remove more deprecated importlib APIs from Python 3.12

[warsaw]

Issue #97850 is the meta issue tracking removals of long deprecated functions from importlib. This ticket tracks just the removals of the following previously deprecated APIs:

• find_loader()
• find_module()
• imp module
• importlib.abc.Finder
• pkgutil.ImpImporter
• pkgutil.ImpLoader

• @brettcannon @ericsnowcurrently

Linked PRs

• gh-98040: Remove just the imp module #98573
• gh-98040: Move the Single-Phase Init Tests Out of test_imp #102561
• gh-98040: Remove find_loader, find_module and other deprecated APIs #98059
• GH-98040: Suppress cross-references to the removed imp module #104131
• gh-98040: Fix importbench: use types.ModuleType() #105743
• [3.12] gh-98040: Fix importbench: use types.ModuleType() (GH-105743) #105754

[warsaw]

Questions:

• importlib.abs.PathEntryFinder has this comment: "We don't define find_spec() here since that would break hasattr checks we do to support backward compatibility." Do we need to define find_spec() in this ABC?

[warsaw]

pkgutil.ImpImporter cannot be removed since pip 22.2.2 still uses it. This is also going to keep pkgutil.ImpLoader and the imp module around. I'm going to pause work on this branch until there's a pip upstream resolution.

[hugovk]

Little reminder: we're a month away from the beta freeze to remove these, or to bump removal to 3.13.

[warsaw]

My plan is to complete this work at the 2023 PyCon sprints.