Move essential backend implementations to _backend #874

	name: Lint

	on:
	pull_request:
	push:
	branches:
	- nightly
	- main
	- release/*
	workflow_dispatch:

	jobs:
	python-source-and-configs:
	uses: pytorch/test-infra/.github/workflows/linux_job.yml@main
	with:
	repository: pytorch/audio
	script: \|
	set -euo pipefail

	echo '::group::Setup environment'
	eval "$("$(which conda)" shell.bash hook)"
	pip install --progress-bar=off pre-commit
	echo '::endgroup::'

	set +e
	pre-commit run --all-files --show-diff-on-failure
	status=$?

	echo '::group::Add Summry'
	if [ $status -ne 0 ]; then
	echo '### Lint failure' >> $GITHUB_STEP_SUMMARY
	echo '```diff' >> $GITHUB_STEP_SUMMARY
	git --no-pager diff >> $GITHUB_STEP_SUMMARY
	echo '```' >> $GITHUB_STEP_SUMMARY
	fi
	echo '::endgroup::'
	exit $status

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