Could use some help here. Always getting a syntax error on the last line but seem to be unable to grasp what's wrong.

< File "python", line 56

return average(results)

^

SyntaxError: invalid syntax>

```
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"]) * 0.1
quizzes = average(student["quizzes"]) * 0.3
tests = average(student["tests"]) * 0.6
score = homework + quizzes + tests
def get_letter_grade(score):
if score >= 90:
return "A"
elif 80 <= score < 90:
return "B"
elif 70 <= score < 80:
return "C"
elif 60 <= score < 70:
return "D"
else:
return "F"
print get_letter_grade(get_average(lloyd))
results = []
def get_class_average(students):
for item in students:
get_average(item)
results.append(get_average(student)
return average(results)
```