Add custom error types #887

	name: checks

	on: [push, pull_request]

	jobs:
	formatting:
	runs-on: ubuntu-latest
	strategy:
	matrix:
	python-version: ["3.9"]
	poetry-version: ["1.5.1"]
	steps:
	- uses: actions/checkout@v2
	- name: Set up Poetry ${{ matrix.poetry-version }}
	uses: abatilo/actions-poetry@v2
	with:
	poetry-version: ${{ matrix.poetry-version }}
	- name: Set up Python ${{ matrix.python-version }}
	uses: actions/setup-python@v4
	with:
	python-version: ${{ matrix.python-version }}
	cache: "poetry"
	- name: Install packages
	run: poetry install
	- name: Check black
	run: make black-check
	- name: Check isort
	run: make isort-check
	linting:
	runs-on: ubuntu-latest
	strategy:
	matrix:
	python-version: ["3.9"]
	poetry-version: ["1.5.1"]
	steps:
	- uses: actions/checkout@v2
	- name: Set up Poetry ${{ matrix.poetry-version }}
	uses: abatilo/actions-poetry@v2
	with:
	poetry-version: ${{ matrix.poetry-version }}
	- name: Set up Python ${{ matrix.python-version }}
	uses: actions/setup-python@v4
	with:
	python-version: ${{ matrix.python-version }}
	cache: "poetry"
	- name: Install packages
	run: poetry install
	- name: Setup mypy
	run: yes \| poetry run mypy cashu --install-types \|\| true
	- name: Run mypy
	run: poetry run mypy cashu --ignore-missing

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