Python is a programming language that's unusually good at the boring jobs: renaming hundreds of files, sorting a messy Downloads folder, turning a spreadsheet export into a summary. By the end of this course you'll have written a script that tidies any folder in seconds — safely.

How the course works

Each lesson explains one idea, then you open a matching exercise file from the exercises folder, fill in the parts marked # TODO, and run the checker. It tells you which tests pass and which don't. Every answer is in exercises/solutions if you're stuck — but try first.

1. Check whether Python is installed

Open a terminal: on Mac, Terminal (in Applications → Utilities); on Windows, PowerShell from the Start menu. Type:

python3 --version

If you see something like Python 3.12.4, you're set (anything 3.9 or newer works). On Windows, if python3 isn't recognised, try python --version and use python wherever this course says python3.

If it's not installed, download it from python.org/downloads. On Windows, tick "Add python.exe to PATH" on the first screen of the installer. On a Mac, macOS may instead offer to install its developer tools when you type python3 — accepting that works too.

2. A text editor for code

Any plain-text editor works, but a code editor makes life much easier. VS Code is free and popular. Open the whole exercises folder in it (File → Open Folder).

3. Move the terminal into the exercises folder

cd means "change directory". Type cd (with a space), drag the exercises folder onto the terminal window, and press Enter. Then type ls (Mac) or dir (Windows) — you should see the exercise files listed.

4. Run and check

Open ex1_hello.py. Change the print line so it prints Hello, Python!, save, then run:

python3 ex1_hello.py python3 check.py 1

The first command runs your script. The second checks it.

EXERCISE 1 — ex1_hello.py

Make the script print exactly Hello, Python!
Run it, then run python3 check.py 1 until you see "exercise complete!".
Try python3 check.py all to see every exercise's starting state.