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

garth gaillard
garth gaillard
3,249 Points
Posted by garth gaillard
garth gaillard
3,249 Points

Unsure why key method isn't working and why i'm getting this error

I'm confused as to why the key method isn't working that Kenneth showed us in the last video. Also the only error message I keep getting is "can't find 'num_teachers' " Which is clearly defined. Any help is appreciated! Thanks!

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):
    for key in dictionary.keys():
        key_amount = len(keys)

    return(key_amount)

2 Answers

Dave Faliskie
Dave Faliskie
17,793 Points
Dave Faliskie
Dave Faliskie
17,793 Points

Your for loop isn't going to get you what you want, your saying for each key in the dictionary set key_amount equal to the length of keys, which is undefined. If you think about it, you don't really care what the keys are just how many there are, because of this the for loop is unnecessary. Try using len() on the dictionary itself 

return len(dictionary)