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Guide

Before Session 3 — Add Python to Your Laptop

This week the agent is going to write you a real program, and you're going to run it yourself. To run a program, your laptop needs Python — a free tool that's quick to install. Please spend about 10 minutes on this before the session.

You do not need to be technical, and you won't be writing any Python yourself. This is just installing the thing that runs the program the agent writes — like installing the engine so you can drive the car. If you get stuck, come 10 minutes early on the night and we'll sort it.

Already have Python? Some laptops (especially Macs) come with it. There's a 30-second check at the bottom — do that and you may have nothing to install.

What you'll need

  • The same laptop you've been using (VS Code + Claude Code already installed)
  • An internet connection
  • About 10 minutes

On Windows

Windows usually does not come with Python, so this is the important one.

  1. Go to https://www.python.org/downloads/
  2. Click the big yellow Download Python button
  3. Open the downloaded file to start the installer
  4. ⚠️ Important: on the very first screen, tick the box at the bottom that says "Add python.exe to PATH" before clicking Install. (This is the step everyone misses — it's what lets you run programs by typing python.)
  5. Click Install Now, let it finish, then click Close

On a Mac

Many Macs already have Python — do the check below first. If the check fails, install it:

  1. Go to https://www.python.org/downloads/
  2. Click the big yellow Download Python button
  3. Open the downloaded file and click Continue / Agree / Install through the steps (the defaults are all fine)
  4. Enter your Mac password if asked, and let it finish

The 30-second check (do this — it tells you it worked)

  1. Open VS Code

  2. Open a terminal: top menu Terminal → New Terminal

  3. Type this and press Enter:

    python --version

  4. If you see something like Python 3.12.1, you're done. 🎉

    If it says "command not found" or opens a store page, try:

    python3 --version

    If that shows a version, great — you'll just use the word python3 instead of python on the night. Jot that down. If neither works, the install didn't take — come a few minutes early and we'll fix it together (on Windows it's almost always the "Add to PATH" tick box from step 4).

Done? Here's your checklist

  • Ran python --version (or python3 --version) and saw a version number
  • Noted which word worked for me: python or python3
  • VS Code + Claude Code still working from previous weeks

Stuck on any of it? That's completely fine. This is the fiddliest setup of the course, and helping each other through it is half the fun. Come a few minutes early and we'll get you going. See you there!