Block to IDs #441

	name: Type hinting with mypy
	on:
	pull_request:
	branches:
	- master
	- '**dev'
	paths:
	- splink/**
	- tests/**
	- pyproject.toml

	jobs:
	mypy:
	runs-on: ubuntu-20.04
	name: Check type hinting with mypy
	steps:
	#----------------------------------------------
	# check-out repo and set-up python
	#----------------------------------------------
	- name: Check out repository
	uses: actions/checkout@v3
	- name: Set up python
	id: setup-python
	uses: actions/setup-python@v4
	with:
	python-version: 3.9.10
	#----------------------------------------------
	# set up environment
	#----------------------------------------------
	- name: Load cached Poetry installation
	uses: actions/cache@v2
	with:
	path: ~/.local
	key: poetry-0
	- name: Install Poetry
	uses: snok/install-poetry@v1
	with:
	version: 1.8.2
	virtualenvs-create: true
	virtualenvs-in-project: true
	installer-parallel: true
	- name: Load cached venv
	id: cached-poetry-dependencies
	uses: actions/cache@v2
	with:
	path: .venv
	key: venv-typehint-${{ runner.os }}-${{ steps.setup-python.outputs.python-version }}-${{ hashFiles('**/poetry.lock') }}-00
	- name: Install dependencies
	if: steps.cached-poetry-dependencies.outputs.cache-hit != 'true'
	run: poetry install --no-interaction --no-root --with=typechecking
	- name: Install library
	run: poetry install --no-interaction
	#----------------------------------------------
	# run mypy
	#----------------------------------------------
	- name: Run mypy
	run: \|
	source .venv/bin/activate
	mypy splink

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