https://www.codecademy.com/courses/python-beginner-en-qzsCL/1/4?curriculum_id=4f89dab3d788890003000096

Error message : get_class_average([alice]) resulted in an error: 'NoneType' object is not iterable

I expected the function get_class_average([lloyd])

would return the averaged value of lloyd's scores but it doesnt work

```
lloyd = {
"name": "Lloyd",
"homework": [90.0, 97.0, 75.0, 92.0],
"quizzes": [88.0, 40.0, 94.0],
"tests": [75.0, 90.0]
}
alice = {
"name": "Alice",
"homework": [100.0, 92.0, 98.0, 100.0],
"quizzes": [82.0, 83.0, 91.0],
"tests": [89.0, 97.0]
}
tyler = {
"name": "Tyler",
"homework": [0.0, 87.0, 75.0, 22.0],
"quizzes": [0.0, 75.0, 78.0],
"tests": [100.0, 100.0]
}
def average(numbers):
#the variable is expected to be a list.
total=sum(numbers)
total=float(total)
return total/len(numbers)
def get_average(student):
#the variable is expected to be a dictionary
ave=0
ave=float(ave)
homework=average(student['homework'])
quizzes=average(student['quizzes'])
tests=average(student['tests'])
ave=0.1*homework+0.3*quizzes+0.6*tests
return ave
def get_class_average(students):
#students is expected to be a list
results=[]
for student in students:
results=results.append(get_average(student))
return average(results)
print(get_class_average([lloyd]))
```