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

num_courses and dictionaries

I don't understand why this code doesn't work. I tried going simpler and it worked in Visual Studio Code but it doesn't work here.

# 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):

    teachers = len(dic.keys())

    return teachers
def num_courses(dic):
    zero = 0
    for nums in dic.values():
        jnums = ' '.join(nums)
        courses = zero += int(jnums)

1 Answer

Brendan Whiting
.a{fill-rule:evenodd;}techdegree seal-36
Brendan Whiting
Front End Web Development Techdegree Graduate 84,735 Points

dic.values() is going to be a list of lists. I printed out dic.values() of the example dictionary and it sent me this:

dict_values([['jQuery Basics', 'Node.js Basics'], ['Python Basics', 'Python Collections']])

So you need some kind of loop inside a loop. I'm also not sure where you're going with joining the items. My strategy was just to flatten out the list of lists into one list, and then return the length of that list.