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

yannis sousanis
yannis sousanis
7,199 Points

help on dictionaries

Ive been working this for hours and I cant pass it

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(a):
    return len(a)
def num_courses(dic):
     number = 0
    for v in dic.values():
        number += 1
    return number

1 Answer

Hi Yannis

Number should += to the length of each list in the dictionary

def num_courses(dic):
    number = 0
    for v in dic.values():
        number += len(v)
    return number

Also its a good habit to describe your variables a bit more, don't use names like 'a','v' and so on. Its ok with few lines of code, but when you write a lot of code, the way you describe your variables can help a lot with readability. Hope this helps