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

need help am failing to get the required courses


# 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(teachers):
    return int(len(teachers))

def num_courses(tt):
    courses = 0
    for value in tt.values():
        courses += len(value)
    return courses

def courses(slist):
    for courses in slist.values():
        course =  list(courses)
        return course

1 Answer

Antonio De Rose
Antonio De Rose
20,884 Points

Not sure how that works, but I was able to get around that issue by doing the below

# the reason for me to have 2 for loops, was to have one flat list, if I stop from the first loop
# and then to append, I would have had a list of lists

#think of it like, the moment you have tt.values(), you result in something lie

# tt = [
# ['jQuery Basics', 'Node.js Basics'],
# ['Python Basics', 'Python Collections']
# ]

# when you loop for the first time, you have a list of lists
# value = ['jQuery Basics', 'Node.js Basics'],
# the above itself will not work, as it is another list
# cause, we are interested in the strings. will have to break till you have a string in hand
# hence loop over again, for the tx to have 'jQuery Basics', 'Node.js Basics'
# append it to courses, the newly created list, for the return
# it will come out of the inner loop, as it had finished the inner loop
# now go to the outer loop, have got the next one remaining, ['Python Basics', 'Python Collections']
# do same

Dict = {
        'Andrew Chalkley': ['jQuery Basics', 'Node.js Basics'],
        'Kenneth Love': ['Python Basics', 'Python Collections']

def num_courses(tt):
    courses = []
    for value in tt.values():
        for tx in value:
    return courses