What I am doing wrong. Please help

# 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(dict):
    num_teachers = 0
    for teacher in dict:
        num_teachers += 1
    return num_teachers

def num_courses(dict):
    num_courses = 0
    for teacher in dict:
        num_courses += len(dict[teacher])
    return num_courses

def courses(dict):
    courses_list = []
    for teacher in dict:
        for course in dict[teacher]:
                courses_list.append(course)
    return course_list