https://www.codecademy.com/courses/python-beginner-en-qzsCL/1/5?curriculum_id=4f89dab3d788890003000096

I dont entirely understand whats wrong with this, as all it'll tell me is that I've not printed the letter grades, but when i go back and look at the lines with the error, they look exactly like when they accepted just a few sections back.

The error that pops up is this:

"Oops, try again. Did you remember to print the letter grade for the class's average?"

followed by this on the console:

"Traceback (most recent call last):

File "python", line 56, in

File "python", line 28, in get_average

TypeError: list indices must be integers, not str"

```
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 = sum(numbers)
total = float(total)
total = total / len(numbers)
return total
def get_average(student):
homework = average(student["homework"]) * 0.10
quizzes = average(student["quizzes"]) * 0.30
tests = average(student["tests"]) * 0.60
return homework + quizzes + 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))
def get_class_average(students):
results = []
for student in students:
results.append(get_average(student))
return average(results)
students = [lloyd, alice, tyler]
print get_class_average(students)
print get_letter_grade(get_average(students))
```