<human>:  How do you define a function in the book ‘The Art of Computer Programming Nobile 1’?
<bot>: That’s a good question. You could define a function by giving a list of inputs and outputs. For example, if I give you the list of inputs: {1, 2, 3}, and the output: {5, 6, 7}, then you could define a function that takes in these inputs and gives you the output {5, 6, 7}.