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

Ralph Hellstern
Ralph Hellstern
6,106 Points
Posted by Ralph Hellstern
Ralph Hellstern
6,106 Points

Question 3 of 5

Hi, I am stuck with question 3 of 5. What is wrong with my code? Thanks in advance.

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(dict):
    return len(dict)

def num_courses(dict):
    counter = 0
    for value in dict.values():
        counter += len(value)
    return counter

def courses(dict):
    list = []
    for value in dict.values():
        list = dict.extend(value)
    return list

1 Answer

Josh Keenan
Josh Keenan
20,315 Points
Josh Keenan
Josh Keenan
20,315 Points

Here's my solution, it uses a for loop to iterate over the values (courses) each teacher has, then for each list of courses it starts a new for loop, to go through the list of their courses and then appends them to the course_list 

def courses(arg):
    course_list = []
    for value in arg.values():
        for i in value:
            course_list.append(i)
    return course_list