8. Part of the Whole


#1



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

the error:
Oops, try again. get_class_average([alice]) resulted in an error: unsupported operand type(s) for +=: 'int' and 'NoneType'

get class averages.


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]
}

def average(numbers):
    total = float(sum(numbers))
    return total / len(numbers)
    
def get_average(student):
    homework = average(student["homework"]) * 0.1
    quizzes = average(student["quizzes"]) * 0.3
    tests = average(student["tests"]) * 0.6
 
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"
    print get_letter_grade(get_average(lloyd))

def get_class_average(students):
    results = 0
    for x in students:
        results +=(get_average(x))
        return avg / len(pupils)
    return average(results)
    print get_class_average(students)

Thanks a Lot !


#2

uhm... lets see, instructions, step 1 you did correctly, step2:
First, make an empty list called results
your code:

results = 0

nice list. Then step 3:
or each student item in the class list, calculate get_average(student) and then call results.append() with that results

so all you need to do is append get_average(student) to results. what is between () in append() is what is appended to a list. I don't see append, or anything similar as asked by the instructions

then step 4 you did correctly:

return average(results)

please do keep in mind, that when a return keyword is reached, the function ends