Hi

i have error in 6/9

get_average(alice) raised the following error: string indices must be integers, not str

why did this error raised?

```
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 = 0
total = sum(numbers)
return float(total)/len(numbers)
def get_average(students):
for st in students:
print st["name"]
homework= average(st["homework"])
quizzes= average(st["quizzes"])
tests= average(st["tests"])
w_average=.1*homework+.3*quizzes+.6*tests
return w_average
print get_average([lloyd, alice, tyler])
```

thanks