My Code is not working and I don’t know why.

```
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]
}
students= [tyler, lloyd, alice]
def average(student):
total= float(sum(student))
total= total/float(len(student))
return total
def get_average(student):
homework=average(student["homework"])
quizzes=average(student["quizzes"])
tests=average(student["tests"])
weighted_total= homework*.1 + quizzes*.3 + tests*.6
return weighted_total
#for student in students:
#student["weighted average"]= get_average(student)
print average(tyler["homework"])
print get_average(alice)
print lloyd
def get_letter_grade(average):
if average >= 90:
return "A"
elif average >= 80:
return "B"
elif average >= 70:
return "C"
elif average >= 60:
return "D"
elif average<60:
return "F"
else:
return "Something's wrong"
print get_letter_grade(get_average(lloyd))
def get_class_average(class_list):
results=[]
for student in class_list:
results.append(get_average(class_list)
average(results)
return results
print get_class_average(students)
```