I feel confused for the last part and I hope you could help me

# The dictionary will look something like:
# {'Andrew Chalkley': ['jQuery Basics', 'Node.js Basics'],
#  'Kenneth Love': ['Python Basics', 'Python Collections']}
#
# Each key will be a Teacher and the value will be a list of courses.
#
# Your code goes below here.
def num_teachers(teacher): 
    number = len(teacher)
    return number
def num_courses(teacher):
    courses = 0
    for course in teacher.values():
        courses += len(course)
    return courses
def courses(teachers): 
    course = []
    for teacher in teachers.values():
        course.extend(teacher)
    return course

def most_courses(teacher): 
    max_courses = len(teacher.values()): 
        if courses > max_courses: 
            name = teacher.update(teacher)
            return name