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

Mikkel Bielefeldt
Mikkel Bielefeldt
3,227 Points

I don't understand

I don't understand this challenge, I feel like I'm some kinda of close but not, and I just can't seem to think of an answer.

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(dic):
    return int(len(dic))

def num_courses(dic):
    result = 0
    for a in dic:
        result += len(dic[a])
    return result

def courses(dic):
    for key in dic:
        dic.pop('key', None)
    return list(dic)

1 Answer

Steven Parker
Steven Parker
229,981 Points

I can see you had a plan, but two issues stand out:

  • if you put quotes around a variable name, it's no longer a variable and just a literal string
  • if you pop all the items from the dictionary, there will be nothing left to return

Your previous function might make a good model to work from. Just instead of counting the courses, this time you will accumulate them into a single list.