Why is the list students = [lloyd, tyler, alice] unnecessary?


#1



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

This code works weather I have the list students = [] or not. Without the list, how does the code know to run through all the dictionaries?


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):
    for number in numbers:
        total = float(sum(numbers))
        total = total/len(numbers)
    return total 

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"
        
    letter_grade = get_letter_grade(get_average(lloyd))
    print letter_grade
    
def get_class_average(students):
    results = []
    for student in students:
        get_average(student)
        results.append(get_average(student))
    return average(results)
    
print get_class_average(students)
print get_letter_grade(get_class_average(students))


#2

It knows to run through a dictionary you call with the function you've created.

For instance:

get_letter_grade(lloyd)

Hope this helps! :smile:


#3

In the final print get_letter_grade(get_class_average(students)) I do not call a list of students but the code comes up with a B from averaging Lloyd, Alice and Tyler but the code knows to pull from all three libraries. How is this?


#4

True, that's fantastically amazing.

I didn't see you do this in your code as in the instruction students = [lloyd, alice, tyler] and yet gives that.

A bug I might want to guess or you might have done so and it's still reading that you did so before.

:smile:


#5

true it work but i dont know whats is going on , i wrote the same code (be my own hand) and it keep telingme that it an error pop that the type ([alice]) supused to be int not srt.
but wene i copy and paset it works


#6

Uhm.. Maybe indentation or something you might be seeing yourself.

You're welcome.

Have fun coding! :slight_smile: