Adds type hints throughout Hatchet and integrate checks with mypy #1

	name: Run mypy-based type checking

	on:
	push:
	branches: [ develop ]
	pull_request:
	branches: [ develop, releases/** ]

	jobs:

	type_check:

	runs-on: ${{ matrix.os }}
	strategy:
	matrix:
	# TODO: add macos-latest
	# TODO: change ubuntu-20.04 back to ubuntu-latest when the following issue is resolved:
	# https://github.com/actions/setup-python/issues/162
	os: [ubuntu-20.04]
	# TODO: add pypy2, pypy3
	python-version: [3.7, 3.8, 3.9, "3.10", "3.11"]

	steps:
	- uses: actions/checkout@v4

	- name: Set up Python ${{ matrix.python-version }}
	uses: actions/setup-python@v5
	with:
	python-version: ${{ matrix.python-version }}

	- name: Install Python3 dependencies
	run: \|
	python -m pip install --upgrade pip pytest
	pip install -r requirements.txt
	# Optional Dependency for HDF Checkpointing
	pip install tables
	python setup.py install
	python setup.py build_ext --inplace
	python -m pip list

	- name: Install mypy
	run: \|
	python3 -m pip install mypy==1.4.1

	- name: Run mypy
	run: \|
	mypy hatchet --pretty

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