The complete beginner's course. Where a worked example prints an exact result, you can predict the output and check it in the browser against the program's own output; where it ends in an error, you name the exception and it is checked by its class. Some Check yourself exercises are checked too: Predict the output, and Put in order, where you arrange the lines and your order is run. The other exercises are shown for you to read — they are not automatically checked.
prediction.stdout/v1, prediction.error_type/v1 and ordering.stdout/v1 pipelines