add lecture 23 after class #80

	on:
	push:
	branches:
	- master

	# Cancel previous runs if a new commit is pushed to the same PR or branch
	concurrency:
	group: ${{ github.ref }} # Group runs by the ref (branch or PR)
	cancel-in-progress: true # Cancel any ongoing runs in the same group

	# Sets permissions of the GITHUB_TOKEN to allow deployment to GitHub Pages and modify PR labels
	permissions:
	contents: read # Read access to repository contents
	pages: write # Write access to GitHub Pages
	id-token: write # Write access to ID tokens

	jobs:
	build_project:
	runs-on: ubuntu-latest
	name: Build project
	steps:
	- name: Checkout project
	uses: actions/checkout@v5
	with:
	fetch-depth: 0 # Fetch all history for all branches and tags

	- name: Build Lean
	uses: leanprover/lean-action@434f25c2f80ded67bba02502ad3a86f25db50709 # v1.3.0
	with:
	auto-config: false
	use-github-cache: false
	use-mathlib-cache: true
	build: true

	- name: Build Documentation
	uses: leanprover-community/docgen-action@b210116d3e6096c0c7146f7a96a6d56b6884fef5 # 2025-06-12
	with:
	homepage: docs

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