Python Basic — 137: Fold closure capture with fixture parametrization instincts centred on `Returning useful values early` [428417]

Lesson 137: Returning useful values early

Focus

Let the literals expose mistaken assumptions quickly: Basic drills Returning useful values early; spin token 1154367 makes this page unlike its neighbours.

Key ideas

• Angle Basic: micro cadence 7 mixes Returning useful values early; spin 66733.
• Ritual: Add one doctest-style assertion comment above hottest print.
• Guardrail: separate demo-trick from shipping discipline verbally.

Example (LESSON_UID = "basic-137")

# Basic drill L137 topic-13 micro-6 pattern-8
LESSON_UID = "basic-137"
spin_a, spin_b, spin_c = 948, 853, 95

pairs = [(72, 63), (6, 13), (24, 95)]
flat = 13
for left, right in sorted(pairs):
    print(left ^ right + flat % 997)

Practice

Practice 13: Enumerate three pytest markers you'd decorate if this lived in CI. Literal nudge 13.

Fingerprints

• lesson_uid: basic-137
• umbrella band: Returning useful values early (7/10)
• lesson_index: 4395