Glossary · Phase 0 · Tools
Check digit
An extra digit computed from the others, so a mistyped number can be caught before it's used, as in the Luhn check on payment cards.
Try it now
Python skips the body on line 1 until line 5 calls the function. Each call gets its own frame with its own spend, clicks and cpc, which disappears when the function returns.
Learn it properly
Functions · Package steps into reusable, testable pieces with inputs and outputs. About 35 minutes.
Other terms from the same lesson
- argument: A value you hand to a function when you call it, like the number in round(3.7).
- function: A named, reusable piece of code that takes inputs and gives back a result.
- return value: What a function hands back when it finishes.
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