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Decoders · difficulty 2 of 3

IBAN validator 🏦

Validate a bank IBAN with the mod-97 rule: move the first four characters to the end, turn letters into numbers (A=10 … Z=35), and check the whole thing leaves remainder 1.

Write it in the browser and press run. Real Python, checked against the expected output, no account needed.

Skills: strings, maths, dicts

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