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

Posted by Mathew Yangang
Mathew Yangang
4,433 Points

returning dictionary

i can't figure out why my code wouldn't work

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(teachers):
    numberOfTeachers=num_teachers.count()
    return numberOfTeachers

1 Answer

Grigorij Schleifer
Grigorij Schleifer
10,365 Points
Grigorij Schleifer
Grigorij Schleifer
10,365 Points

Hi Mathew,

the num_teachers method expects a set as its parameter. You are trying to call count() on your freshly declared methods name and I am not sure you can do it. You need a method that counts the keys of the set and returns this number.

Sadly, a set has no attribute count() that could do it for you. But python does.

You can use the num_teachers parameter teachers as an argument for the len() function. This function will count the keys (how many teachers are in the set) and you can return that number.

I would use this code:

def num_teachers(teachers):
    number_of_teachers = len(teachers)
    return number_of_teachers