When I Save & submit code, it gives the result:

83.8666666667

B

None

Which seems to be OK. But I Receive a problem which says:

"Oops, try again.

One of the following is missing or broken when we tried to use it:

alice, lloyd, tyler, students, get_class_average, get_letter_grade"

My code is the following:

```
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):
total = float(sum(numbers))
return total / len(numbers)
def get_average(student):
homework = average(student["homework"])
quizzes = average(student["quizzes"])
tests = average(student["tests"])
return .1 * homework + .3 * quizzes + .6 * tests
def get_letter_grade(score):
if score >= 90:
return "A"
elif score >= 80:
return "B"
elif score >= 70:
return "C"
elif score >= 60:
return "D"
else:
return "F"
def get_class_average(students):
results=[]
for x in students:
get_average(x)
results.append(get_average(x))
return average(results)
classList = [lloyd, alice, tyler]
print get_class_average(classList)
print get_letter_grade(get_class_average(classList))
```