```
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]
}
# Add your function below!
def average(numbers):
total = float(sum(numbers))
x = ((total) / (len(numbers)))
return x
def get_average(student):
homework = average(student['homework'])
quizzes = average(student['quizzes'])
tests = average(student['tests'])
return (homework*0.1)+(quizzes*0.3)+(tests*0.6)
def get_letter_grade(score):
score = float(score)
if score >= 90:
return "A"
elif score >= 80:
return "B"
elif score >= 70:
return "C"
elif score >= 60:
return "D"
else:
return "F"
print get_letter_grade(get_average(lloyd))
print get_letter_grade(get_average(alice))
print get_letter_grade(get_average(tyler))
def get_class_average(students):
students = [lloyd, alice, tyler]
results = []
for student in students:
get_average(student)
return results.append(get_average(students))
return average(results)
```

I get get_class_average(alice)] resulted in an error: list indices must be integers, not str.

so I tried making students = [lloyd, alice, tyler] into float() but didn't work, how i'm I supposed to this?

why doesn't it gives an error for lloyd but does for alice?