Inconsistent import behavior when concurrent.futures.InterpreterPoolExecutor not exist

[aisk]

Bug report

Bug description:

When the _interpreters module which under the hood to implement InterpreterPoolExecutor does not exist, import concurrent.futures.InterpreterPoolExecutor will result None, instead of ImportError.

A PR is on the way to address this.

CPython versions tested on:

CPython main branch

Operating systems tested on:

No response

Linked PRs

• gh-136380: Fix import behavior for concurrent.futures.InterpreterPoolExecutor #136381
• [3.14] gh-136380: Fix import behavior for concurrent.futures.InterpreterPoolExecutor (GH-136381) #136420