speedup for count_nested by=None #61

	# This workflow will install Python dependencies, run tests and report code coverage with a variety of Python versions
	# For more information see: https://help.github.com/actions/language-and-framework-guides/using-python-with-github-actions

	name: Unit test and code coverage

	on:
	push:
	branches: [ main ]
	pull_request:
	branches: [ main ]

	jobs:
	build:

	runs-on: ubuntu-latest
	strategy:
	matrix:
	python-version: ['3.9', '3.10', '3.11', '3.12']

	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 dependencies
	run: \|
	sudo apt-get update
	python -m pip install --upgrade pip
	pip install -e .[dev]
	if [ -f requirements.txt ]; then pip install -r requirements.txt; fi
	- name: Run unit tests with pytest
	run: \|
	python -m pytest --cov=nested_pandas --cov-report=xml
	- name: Upload coverage report to codecov
	uses: codecov/codecov-action@v4
	with:
	token: ${{ secrets.CODECOV_TOKEN }}

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