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Python Python Collections (Retired) Dictionaries Teacher Stats

Laknath Gunathilake
Laknath Gunathilake
1,860 Points
Posted by Laknath Gunathilake
Laknath Gunathilake
1,860 Points

can't seem to get a full list from the dictionary keys

def courses(my_dict): slist=[] for value in my_dict.values(): slist.append(value) return slist

when I run this code, it says returned only five courses, but expected 18

teachers.py 
# The dictionary will be something like:
# {'Jason Seifer': ['Ruby Foundations', 'Ruby on Rails Forms', 'Technology Foundations'],
#  'Kenneth Love': ['Python Basics', 'Python Collections']}
#
# Often, it's a good idea to hold onto a max_count variable.
# Update it when you find a teacher with more classes than
# the current count. Better hold onto the teacher name somewhere
# too!
#
# Your code goes below here.
def most_classes(my_dict):
    max_teacher=''
    max_count=0
    for teacher in my_dict:
        count=len(my_dict[teacher])
        if count>max_count:
            max_teacher=teacher
            max_count=count
    return max_teacher 
def num_teachers(my_dict):
    return len(my_dict.keys())
def stats(my_dict):
    stat=[]
    for teacher in my_dict:
        count=len(my_dict[teacher])
        stat.append([teacher,count])
    return stat 
def courses(my_dict):
        slist=[]
        for value in my_dict.values():
             slist.append(value)
        return slist

3 Answers

Steven Parker
Steven Parker
231,269 Points
Steven Parker
Steven Parker
231,269 Points

Remember that each of the values in the dict is itself a list. When you append a list, you get only one new item.

:point_right: Instead of append, you might want to use extend.

Jeremy Hill
Jeremy Hill
29,567 Points
Jeremy Hill
Jeremy Hill
29,567 Points

This challenge can be a little tricky, but your code was real close- I tweaked it a little bit:

def courses(my_dict):
        slist=[]
        for teacher in my_dict.values():
            for value in teacher:
                slist.append(value)
        return slist
Aby Abraham
PLUS
Aby Abraham
Courses Plus Student 12,531 Points
Aby Abraham
Aby Abraham
Courses Plus Student 12,531 Points

My Answer:

def most_classes(dict):
    max_count = 0
    str = ""
    alist = dict.values()
    for key, value in dict.items():
        if len(value) > max_count:
            max_count = len(value)
            str = key
    return str


def num_teachers(dict):
    return len(dict.keys()) 


def stats(dict):
    slist = []
    for key, value in dict.items():
        slist.append([key, len(value)])
    return slist


def courses(dict):
    clist = []
    for value in dict.values():
        clist.extend(value)
    return clist