A $\_\_\_\_\_\_\_\_\_\_\_$ is a reusable block of code that performs a certain action $($or actions$).$ They are used to accomplish the same tasks repeatedly. Instead of copy$-$pasting the same lines multiple places in your code, you should use a function. also divide complex code into smaller parts, which make it far more readable and maintainable. An example from excel is an $$if statement$$

output statement$$

List$$

program$$

Function$$