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

Posted by Rosu Calin
Rosu Calin
935 Points

This works on my computer but not here? Adding integer to list not possible

I can't get this to work. It works and returns the right values when using Python from my PC..

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

def num_courses(dic):
    sum = 0
    for key_value in dic:
        y  = dic[key_value]
        sum += y

    return sum

2 Answers

Umesh Ravji
Umesh Ravji
42,386 Points
Umesh Ravji
Umesh Ravji
42,386 Points

Hi Rosu, I'm not sure why it works on your PC, it doesn't work on mine :)

def num_courses(dic):
    sum = 0
    for key_value in dic:
        y  = dic[key_value]  # y is a list, not a number (use len function to get count of courses)
        sum += y
    return sum
Steven Parker
Steven Parker
231,248 Points
Steven Parker
Steven Parker
231,248 Points

I don't usually provide spoilers, but you are already so close! And Umesh added a good comment, but did not apply it to the code. Also, you don't really need the variable "y":

def num_courses(dic):
    sum = 0
    for key_value in dic:
        sum += len(dic[key_value])
    return sum