human
I am working on the file "09/.ipynb_checkpoints/09 - Functions-checkpoint.ipynb".
The first task is:
Horrifying, right? Thank goodness for functions.
Writing your own functions
I've always been kind of jealous of len(...) and its crowd. It seemed unfair that Python made a list of cool, important functions, and neither me nor you had any say in the matter. What if I want a function that turns all of the periods in a sentence into exclamation points, or prints out a word a hundred million times?
Well, turns out that isn't a problem. We can do that. Easily! And we will. If you can type def and use a colon, you can write a function.
A function that you write yourself looks like this:
Can you write Python code for it?
assistant
#Here if I want a function that turns all of the periods in a sentence into exclamation points, or prints out a word a hundred million times.

# A function to multiply a number by two
def double(number):
    bigger = number * 2
    return bigger
#what happens inside the function STAYS inside the function
#unless you use return, you don't know what happens within the function