Add annotations import, `mlbench.util` docstring #3

	name: Lint and test mlbench

	on:
	push:
	branches:
	- master
	pull_request:
	branches:
	- master

	jobs:
	lint:
	runs-on: ubuntu-latest
	env:
	MYPY_CACHE_DIR: "${{ github.workspace }}/.cache/mypy"
	RUFF_CACHE_DIR: "${{ github.workspace }}/.cache/ruff"
	PRE_COMMIT_HOME: "${{ github.workspace }}/.cache/pre-commit"
	steps:
	- uses: actions/checkout@v4
	with:
	fetch-depth: 0
	- name: Set up Python and dependencies
	uses: actions/setup-python@v4
	with:
	python-version: 3.11
	cache: pip
	cache-dependency-path: \|
	requirements-dev.txt
	pyproject.toml
	- name: Install dependencies
	run: \|
	pip install -r requirements-dev.txt
	pip install -e . --no-deps
	- name: Cache pre-commit tools
	uses: actions/cache@v3
	with:
	path: \|
	${{ env.MYPY_CACHE_DIR }}
	${{ env.RUFF_CACHE_DIR }}
	${{ env.PRE_COMMIT_HOME }}
	key: ${{ hashFiles('requirements-dev.txt', '.pre-commit-config.yaml') }}-linter-cache
	- name: Run pre-commit checks
	run: pre-commit run --all-files --verbose --show-diff-on-failure
	test:
	name: Test mlbench on ${{ matrix.os }}
	runs-on: ${{ matrix.os }}
	strategy:
	fail-fast: false
	matrix:
	os: [ ubuntu-latest, macos-latest, windows-latest ]
	steps:
	- uses: actions/checkout@v4
	with:
	fetch-depth: 0
	- name: Set up oldest supported Python on ${{ matrix.os }}
	uses: actions/setup-python@v4
	with:
	python-version: 3.9
	- name: Run tests on oldest supported Python
	run: \|
	python -m pip install ".[dev]"
	pytest

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