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Python Python Collections (2016, retired 2019) Dictionaries Teacher Stats

Evgeniy Vdovenko
Evgeniy Vdovenko
1,346 Points

dictionaries. 5 of 5

Hi everybody! Im trying to pass the challenge in dictionaries 5/5. Ive done the code and tested it in PyCharm. It works there, but not in here. So i tried to play a bit with naming variables and other staff, but it still works in PyCharm but not here. I guess that im using some method which is not correct for this exercise but im not sure. Please help me out!

# 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 (tc):
    teacher_courses = {}
    num_teachers = 0
    for teacher in tc:
        num_teachers += 1

    return num_teachers

def num_courses (teacher_courses):
    num_courses = 0
    for course in teacher_courses.values():
        num_courses = num_courses + len(course)

    return num_courses

def courses (teacher_courses):
    courses = []
    for courses_list in teacher_courses.values():
        for course1 in courses_list:
            if course1 in courses:

    return courses

def most_courses (teacher_courses):
    max_count = 0
    most_courses = str()
    for teacher, course in teacher_courses.items():
        if len(course) > max_count:
            max_count = len(course)
            most_courses = teacher

    return most_courses

def stats (teacher_courses):
    stats = list()
    for teachers_name, course in teacher_courses.iteritems():
        inner_list = list()
        inner_list.insert(0, teachers_name)
        inner_list.insert(1, len(course))
        if inner_list in stats:

    return stats

2 Answers

You're calling iteritems(), which is only in python 2, not 3. Changing it to items() should fix the issue.

Evgeniy Vdovenko
Evgeniy Vdovenko
1,346 Points

Great man! That worked out! Thanks a lot!

Matthieu Tripoli
Matthieu Tripoli
18,677 Points

You can simplify the code by doing the following:

def stats(teacher_dict): list = [] for teacher, courses in teacher_dict.items(): # Pulls the teacher and their courses list.append([teacher, len(courses)]) # Add to list the teacher and the number of courses return list