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

Gabri Chodosh
Gabri Chodosh
1,487 Points

How to create single list of courses?

I wrote:

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

Why doesn't this function work to create a single list of all the courses in the dictionary?

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(dict):
    return len(dict.keys())
def num_courses(dict):
    return sum(len(value) for value in dict.values())
def courses(dict):
    list = []
    for value in dict.values()
        list.extend(value)
    return list

1 Answer

You're doing excellent! However, it appears that you are missing a colon in front of this line:

for value in dict.values()

Python is very picky, and it will throw errors if it doesn't like something!

I hope this helps! :grin: :zap: ~Alex