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

eestsaid
eestsaid
1,311 Points
Posted by eestsaid
eestsaid
1,311 Points

Code Challenge - Teacher Stats task 5

I'm stuck on task 5. I can get this dictionary to be converted to a list but having trouble replaceing the sublist with the length of the sublist.

def stats(teachers):
    teacher_list = []
    for i in teachers.items():
        teacher_list += i
        for j in teacher_list:
            teacher_list.replace(len(teacher_list[j]))
    return(teacher_list)

I tried another approach which drew from task 4 using "key, value" variables but without success

def stats(teachers):
    teacher_list = []
    for key, value in teachers.items():
        teacher_list.append([key, len(teachers[value])])
    return(teacher_list)

1 Answer

Steven Parker
Steven Parker
231,236 Points
Steven Parker
Steven Parker
231,236 Points

You're second try is very close! But when you reference "teachers[value]", you're attempting to use the value as a key. What you probably meant to do was "teachers[key]", but that's not even needed since you already have "value" and can use it directly.

        teacher_list.append([key, len(value)])
eestsaid
eestsaid
1,311 Points
eestsaid
eestsaid
1,311 Points

Thanks Steven. That fixed it. I saw the key, value approach in a few youtube videos and the like and though it works I don't fully understand the sequence of operations. Are either of the following the correct intuition?

  • from 'teachers' take the first key and value pair in the dict and append it to 'teacher_list' then repeat; or
  • from 'teachers' take all the keys successively in the dict and append to 'teacher_list' and then take values successively in the dict and append to 'teacher_list'

Thanks again

Steven Parker
Steven Parker
231,236 Points
Steven Parker
Steven Parker
231,236 Points

The first description is more accurate. The keys and and sizes are being appended together inside a mini-list.