The following code outputs

get_average(alice) raised the following error: ‘float’ object is not iterable.<

But why?

```
# Add your function below!
def average(numbers):
total = float(sum(numbers))
length = len(numbers)
return total/length
def get_average(student):
homework = average(student["homework"])
quizzes = average(student["quizzes"])
tests = average(student["tests"])
return sum(0.1*homework+0.3*quizzes+0.6*tests)
```