Read, predict, fix.

Most platforms make you write code. PythonCook makes you read, predict, and fix it first. Each activity below is a live sample.

• Tier 0 · Predict the outputWhat does the loop total?predict-output
• Tier 0 · Predict the outputWhat does the slice give?predict-output
• Tier 1 · Find the bugSpot the out-of-range linefind-the-bug
• Tier 1 · Explain this codeExplain what evens doesexplain-this-code
• Tier 1 · Parsons problemRebuild the biggest functionparsons
• Tier 1 · Fix the bugFix the average functionfix-the-bug
• Tier 2 · Refactor the AI's codeRefactor the shipping feerefactor
• Tier 2 · Write the test firstTest clamp before you trust itwrite-the-test-first
• Tier 1 · Free buildBuild initialsfree-build