**Hi Gents,**

I need your help in order to continue my training on Python. I stuck on the above mentioned exercise for a not clear reason..at least to me...

Here is link to the exercise I stuck at:

**Error Message Says:**

Oops, try again. One of the following is missing or broken when we tried to use it: alice, lloyd, tyler, students, get_class_average, get_letter_grade

The code run and the output was as follows:

83.8666666667

B

None

**Here is the Code**

```
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)
return total/len(numbers)
def get_average(student):
homework= average(student["homework"])
quizzes= average(student["quizzes"])
tests= average(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))
def get_class_average(students):
results=[]
for stu in students:
results.append(get_average(stu))
return average(results)
print get_class_average([alice, lloyd, tyler])
class_grade= get_class_average([alice, lloyd, tyler])
print get_letter_grade(class_grade)
```