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Python Python Collections (Retired) Dictionaries Teacher Stats

Pei-Ying Lin
Pei-Ying Lin
2,017 Points
Posted by Pei-Ying Lin
Pei-Ying Lin
2,017 Points

Dictionary teacher and class cannot pass

Hey this is my first time asking a question. Can I know what's wrong with the following code? I ran it with IDLE and got what I want but cannot pass the challenge. Thanks!

dict1 = {'Jason Seifer': ['Ruby Foundations', 'Ruby on Rails Forms', 'Technology Foundations'],'Kenneth Love': ['Python Basics', 'Python Collections']}

def most_classes(dic): teacher = [] x = [] for i in dic: x.append(len(dic[i])) teacher.append(i) ind = x.index(max(x)) return teacher[ind]

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

def stats(dic): teacher = [] x = [] for i in dic: x.append(len(dic[i])) teacher.append(i) list1 = teacher + x return list1

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(dic):
    teacher = []
    x = []
    for i in dic:
        x.append(len(dic[i]))
        teacher.append(i)
    ind = x.index(max(x))
    return teacher[ind]

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

def stats(dic):
    teacher = []
    x = []
    for i in dic:
        x.append(len(dic[i]))
        teacher.append(i)
    list1 = teacher + x 
    return list1

1 Answer

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

You're close. But instead of concatenating separate lists of teachers and courses, you want to create a list where each element is itself a list of one teacher and one course count. That can be done using just one line inside the loop.

:information_source: Now your two lists could be interleaved, but that involves facilities that haven't been introduced in the course. So don't use this to pass the challenge, but just for fun it would be:

    list1 = map(list, zip(teacher, x))