Functions: Stop Writing the Same Code Twice

You have written the same print(f"Hello, {name}!") line three times in your code already. Not a big deal with one line. But what happens when the thing you keep repeating is 15 lines long? What happens when you find a bug in it and have to fix it in six different places? What happens when you forget to fix one of them? This is not a hypothetical. This is what happens in real codebases when people don't use functions. Code gets copied, pasted, modified slightly, and then something breaks and nobo