{"id":"set-cardinality-uniqueness-idiom","text":"The `len(set(...)) == 1` idiom is used to check whether all elements share a single value (e.g., all letters on one keyboard row) and recurs across multiple solutions in this repo.","truth_value":"IN","source":"entries/2026/06/06/keyboard-row-solution.md","source_url":"","source_hash":"","justifications":[],"dependents":[],"metadata":{},"created_at":"","updated_at":"","reviewed_at":"","verified_at":"","retracted_at":"","explanation":{"steps":[{"node":"set-cardinality-uniqueness-idiom","truth_value":"IN","reason":"premise"}]}}