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

Kade Carlson
Kade Carlson
5,928 Points
Posted by Kade Carlson
Kade Carlson
5,928 Points

Not sure why this is wrong

What should I have done here instead?

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(dictionary):
    return len(dictionary.keys())

def num_courses(dictionary):
    return len(list(dictionary.values()))

1 Answer

Stuart Wright
Stuart Wright
41,119 Points
Stuart Wright
Stuart Wright
41,119 Points

Note that list(dictionary.values()) will return a list of lists. Using the example dictionary given in the comments, it would give:

[['Python Basics', 'Python Collections'], ['jQuery Basics', 'Node.js Basics']]

The length of this list is 2, because it contains 2 elements. You need to find a way to count the inner elements instead.