Subshells implemented using tornado event loops on 6.x branch #3335

Job	Run time
Test Lint	1m 2s
build (ubuntu-latest, 3.9)	4m 54s
build (ubuntu-latest, 3.13)	5m 0s
check_release	1m 43s
Make SDist	23s
build (windows-latest, 3.9)	7m 55s
test_docs	46s
build (windows-latest, 3.13)	7m 18s
Test Minimum Versions	2m 29s
build (macos-latest, 3.9)	5m 16s
Test Prereleases	2m 10s
build (macos-latest, 3.13)	9m 44s
test_without_debugpy (ubuntu-latest, 3.9)	12m 14s
build (ubuntu-latest, pypy-3.9)	9m 18s
link_check	1m 57s
build (macos-latest, 3.10)	7m 38s
build (ubuntu-latest, 3.11)	4m 39s
build (ubuntu-latest, 3.12)	6m 11s
Install from SDist and Test	2m 22s
coverage	0s
	1h 32m 59s

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