Calculating Class Averages

Problem Statement

Write a function called calculate_class_averages that takes a dictionary, classrooms, containing student exam scores for different classes. Your function should return a new dictionary where the keys are class names and the values are the average exam scores for that class. After implementing your function, use pytest to see if you pass all the tests. If a classroom has 0 students in it then it should return 0.

Example Input

{
    "Math": {
        "Alice": [85, 90, 78],
        "Bob": [72, 88, 91],
        "Charlie": [95, 100, 92]
    },
    "Science": {
        "Alice": [80, 85, 88],
        "Bob": [78, 82, 85],
        "Diana": [90, 91, 89]
    },
    "History": {
        "Charlie": [70, 75, 80],
        "Diana": [88, 92, 84]
    }
}

Example Output

{
    "Math": 88.17,
    "Science": 85.67,
    "History": 81.5
}

Example Input

{
    "Math": {},
    "Science": {
        "Alice": [80, 85, 88],
        "Bob": [78, 82, 85]
    }
}

Example Output

{
    "Math": 0,
    "Science": 83.0
}