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

Robert Gettings
Robert Gettings
1,902 Points
Posted by Robert Gettings
Robert Gettings
1,902 Points

Problem with the maximum value

Tryed this out in workbench and it works there, but doesnt in the test, whats the problem?

teachers.py 
# 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(dictionary_of_teachers):

    num_teachers = 0

    for teacher in dictionary_of_teachers.keys():
        num_teachers += 1

    return num_teachers

def num_courses(dictionary_of_teachers):


    course_list = []

    for course in dictionary_of_teachers.values():

        course_list.extend(course)

    num_courses = len(course_list)

    return num_courses

def courses(dictionary_of_teachers):

    course_list = []

    for course in dictionary_of_teachers.values():

        course_list.extend(course)

    return course_list

def most_courses(dictionary_of_teachers):

    v, k = max((v, len(k)) for v, k in dictionary_of_teachers.items())

    teacher_with_most_courses = v

    return teacher_with_most_courses
Robert Gettings
Robert Gettings
1,902 Points
Robert Gettings
Robert Gettings
1,902 Points

Found the problem myself, I used:

def most_courses(dictionary_of_teachers):

    maxcount = max(len(v) for v in dictionary_of_teachers.values())

    for k, v in dictionary_of_teachers.items():
        if len(v) == maxcount:
            return k

1 Answer

Tonye Jack
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.a{fill-rule:evenodd;}techdegree
Tonye Jack
Full Stack JavaScript Techdegree Student 12,469 Points
Tonye Jack
.a{fill-rule:evenodd;}techdegree
Tonye Jack
Full Stack JavaScript Techdegree Student 12,469 Points

can do all off them with one liners 

num_teachers = lambda arg: len(arg.keys())
num_courses = lambda arg: sum([len(c) for c in arg.values()])
courses = lambda arg: [c for s in arg.values() for c in s]
most_courses = lambda arg: [t for t, c in sorted(arg.items(), key=lambda a: len(a[1]), reverse=True)][0]
stats = lambda arg: [[t, len(c)] for t, c in arg.items()]