Allowing t0 and t1 to be None in index_on and related methods. #15

	name: Style
	on:
	push:
	branches:
	- main
	pull_request:
	types: [opened, synchronize, reopened, ready_for_review]
	branches:
	- '**'

	jobs:

	build-and-test:
	name: style
	runs-on: ubuntu-latest
	if: github.event.pull_request.draft == false

	steps:
	- uses: actions/checkout@v3

	- name: Configure Python
	uses: actions/setup-python@v4
	with:
	python-version: '3.11'
	cache: 'pip'
	cache-dependency-path: setup.py

	- name: Install flake8
	run: \|
	python --version
	python -m pip install flake8

	- name: Run style checking
	run: \|
	python -m flake8 --version
	python -m flake8

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