fix: force return types #119

	on:
	# run on all pushes to any branch
	push:
	paths:
	# Only run on changes to source or test python files and environment.yml
	- "fractopo/**.py"
	- "tests/**.py"
	- ".github/workflows/**.yaml"
	- "pyproject.toml"
	- "environment.yaml"

	jobs:
	conda-environment-install:
	timeout-minutes: 30
	strategy:
	fail-fast: false
	matrix:
	python-version: ["3.9", "3.10", "3.11"]
	platform: ["ubuntu-latest", "macos-latest", "windows-latest"]

	runs-on: ${{ matrix.platform }}
	defaults:
	run:
	shell: bash -l {0}
	steps:
	- uses: actions/checkout@v4
	- uses: mamba-org/setup-micromamba@v1
	with:
	micromamba-version: "1.3.1-0"
	environment-file: environment.yaml
	init-shell: >-
	bash
	powershell
	cache-environment: true
	post-cleanup: "all"
	create-args: >-
	python=${{ matrix.python-version }}
	- name: Run unit tests
	run: \|
	# Test package import
	python -c 'import fractopo'
	# Test module entrypoint
	python -m fractopo --help
	# Run unittests with pytest
	pytest -v

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