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

Julian Silvestri
Julian Silvestri
4,214 Points
Posted by Julian Silvestri
Julian Silvestri
4,214 Points

Teacher Stats Challenge.... im so confused

I am trying to do the first challenge of the 5 required... cant seem to pass it... Not sure what I am missing...

please help

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(arg1):
    number_of_keys = 0
    for x in arg1.keys():
        number_of_keys += 1
    return number_keys # <- [MOD: should be number_of_keys - srh]

3 Answers

Steve Hunter
Steve Hunter
57,712 Points

Hi Julian,

If you access the dictionary using its .keys() method, you can pass that into a len() method and return the result. No need for a loop.

Something like:

def num_teachers(dict):
    return len(dict.keys())

I hope that makes sense.

Steve.

Steve Hunter
Steve Hunter
57,712 Points

Incidentally, your code is fine but you returned a variable of a different name. I'll add a comment in the code in your question.

This is the same as your code and works fine. 

def num_teachers(dict):
    count = 0
    for key in dict.keys():
        count += 1
    return count
Steve Hunter
Steve Hunter
57,712 Points

No problem! This set of challenges is tough!! :+1:

Herman Brummer
Herman Brummer
6,414 Points
Herman Brummer
Herman Brummer
6,414 Points 
def num_teachers(dictionary_list):
    # number of teachers
    return len(dictionary_list)