Level 9 · Lesson 75: Test it yourself

What the lesson explains

Test it yourself. Done means you saw it work.

Done? Prove it.. An agent can say it works when it does not. run it yourself; look with your eyes; then it is done.

What you do first

Run it yourself. In the practice terminal, type python hello.py at the prompt PS C:\Users\you\Documents\my-project> and the computer answers: File "hello.py", line 2 / print("Hello again!" / SyntaxError: '(' was never closed.

The files on the practice computer

This lesson works in one folder. At the start, Documents\my-project holds backups\, club\, games\, images\, my-games\, greet.py, hello.py, hi.py, list.txt, notes.txt.

Along the way you save hello.py in Documents\my-project. Lesson 76 opens with the files just as you leave them.

What you practise

Try it, "Run it yourself": In the practice terminal, type python hello.py at the prompt PS C:\Users\you\Documents\my-project> and the computer answers: File "hello.py", line 2 / print("Hello again!" / SyntaxError: '(' was never closed.

Fix it, "Give it the clue": Tell the agent what went wrong in hello.py. One clear prompt: "In my-project, hello.py says SyntaxError: '(' was never closed, on line 2. Fix it. Done when it prints Hello again!"

Try it, "Fix, then test again": The pretend agent says: "Here is the fix: one bracket on line 2. May I change hello.py?" It asks to change hello.py. The right answer is Allow: it does what you asked, and nothing more. Then: In the practice terminal, type python hello.py at the prompt PS C:\Users\you\Documents\my-project> and the computer answers: File "hello.py", line 2 / print("Hello again!" / SyntaxError: '(' was never closed.

In your head, "Who says done?": Who decides that the work is done? The answer: "You, after you test it".

What PlayBuddy and PlayType say

PlayType: "The agent says it works? Do not just believe it. Test it yourself!"

PlayBuddy: "Run the program, look with your own eyes, then it is done."

Help in every lesson

Everything happens on a pretend computer in your browser, so nothing touches your real files. PlayBuddy and PlayType stand beside the board, cheer you on and say when it is your turn.

A green ring shows where to click the first time. After that you do it on your own, and if you slip twice the ring comes back.

Stars

The lesson has 5 things to do. Up to one slip in ten gives three stars, up to one in four gives two, and finishing always gives at least one. Stars and progress are saved in this browser only; there is no account.

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