Let's review the instructions and see where you went wrong...

Instructions

* First, def a function called cube that takes an argument called number. Don't forget the parentheses and the colon!

* Make that function return the cube of that number (i.e. that number multiplied by itself and multiplied by itself once again).

* Define a second function called by_three that takes an argument called number.

* if that number is divisible by 3, by_three should call cube(number) and return its result. Otherwise, by_three should return False.

Your first function takes care of points 1 and 2. But that's when things begin to break down. See if you can put the code right by following this example pattern:

```
def by_three(number):
if number % 3 == 0: # note the % (remainder) operator
return cube(number)
else:
return False
```

Now we need to test our work:

```
print by_three(11)
print by_three(12)
print by_three(13)
```