I suspect that there's something wrong with the site; code not passing. most_courses task 4/5

def num_teachers(dictionary):
    return len(dictionary)

def num_courses(dictionary):
    total_courses = 0

    for courses in dictionary.values():
        total_courses += len(courses)

    return total_courses

def courses(dictionary):
    course_list = []

    for courses in dictionary.values():
        course_list.extend(courses)

    return course_list

def most_courses(dictionary):
    max_count = 0
    busiest_teacher = ""

    for teacher, courses in dictionary.items():
        if len(courses) > max_count:
            max_count = len(courses)
            busiest_teacher = teacher

    return busiest_teacher

def stats(dictionary):
    quick_list = []

    for teacher, courses in dictionary.items():
        quick_list.append([teacher, len(courses)])

    return quick_list