Add types for Node.predecessor(), Tree._clone(), Tree.subtree() and Tree.to_dict() #121

	# This workflow will install Python dependencies, run tests and lint with a variety of Python versions
	# For more information see: https://docs.github.com/en/actions/automating-builds-and-tests/building-and-testing-python
	name: Package testing

	on:
	push:
	branches: [ "master", "dev" ]
	pull_request:
	types: [opened, synchronize, reopened]

	jobs:
	build-compat:
	runs-on: ubuntu-20.04
	strategy:
	fail-fast: false
	matrix:
	python-version: ["3.6", "3.7"]
	steps:
	- uses: actions/checkout@v4
	- name: Set up Python ${{ matrix.python-version }}
	uses: actions/setup-python@v5.4.0
	with:
	python-version: ${{ matrix.python-version }}
	- name: Install dependencies
	run: \|
	if [ -f requirements.txt ]; then pip install -r requirements.txt; fi
	if [ -f requirements-t-pre37.txt ]; then pip install -r requirements-t-pre37.txt; fi
	- name: Test with nosetest
	run: \|
	./scripts/testing.sh
	build-latest:
	runs-on: ubuntu-22.04
	strategy:
	fail-fast: false
	matrix:
	python-version: ["3.8", "3.9", "3.10", "3.11", "3.12", "3.13"]
	steps:
	- uses: actions/checkout@v4
	- name: Set up Python ${{ matrix.python-version }}
	uses: actions/setup-python@v5.4.0
	with:
	python-version: ${{ matrix.python-version }}
	- name: Install dependencies
	run: \|
	python -m pip install --upgrade pip
	if [ -f requirements.txt ]; then pip install -r requirements.txt; fi
	if [ -f requirements-t.txt ]; then pip install -r requirements-t.txt; fi
	- name: Lint with flake8
	run: \|
	./scripts/flake8.sh
	- name: Test with pytest
	run: \|
	pytest

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