```
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!
student = ['lloyd','alice','tyler']
def average():
avg = float(sum(result()))/len(result())
print (avg)
def get_class_average(student):
result = []
for key in student:
result.append(get_average(student))
return average(result)
def get_average(student):
homework = float(sum(student['homework']))/len(student['homework'])
quizzes = float(sum(student['quizzes']))/len(student['quizzes'])
tests = float(sum(student['tests']))/len(student['tests'])
return 0.1 * homework + 0.3 * quizzes + 0.6 * 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'
get_letter_grade(get_average(lloyd))
```

my code runs with saying " list indices must be integers, not str

plz help