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

Posted by behar
behar
10,800 Points

This works in the shell..

This works perfectly fine in the shell, but the checker dosent like it. Anybody?

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(var):
    test = 0
    for teachers in var:
        test += 1
    return test

def num_courses(var):
    test1 = []
    for value in var.values():
        test1.append(value)
    return len(test1)

3 Answers

David Dzsotjan
David Dzsotjan
6,405 Points
David Dzsotjan
David Dzsotjan
6,405 Points

Hi! I think the problem is that you append not elements, but whole lists to your original list. Instead, I'd write

def num_courses(var):

    test1 = []

    for value in var.values():
        test1 += value
    return len(test1)

so you just add up your lists and won't have lists nested in lists.

behar
behar
10,800 Points

Thats weird but thank you!

David Dzsotjan
David Dzsotjan
6,405 Points
David Dzsotjan
David Dzsotjan
6,405 Points

No problem :) - does it work this way?

behar
behar
10,800 Points

Yup it passed