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

angel moreta
angel moreta
2,912 Points
Posted by angel moreta
angel moreta
2,912 Points

ok i need a hint

challenge:That one wasn't too bad, right? Let's try something a bit more challenging. Create a new function named num_courses that will receive the same dictionary as its only argument. The function should return the total number of courses for all of the teachers.

I know the challenge says I don't have to create a dict, but i added one to the code "my_teachers" so you guys can see more clearly my point of view here. Something else I'll drop down below the output I'm getting from my terminal and I am also using my text editor ATOM, since i don't feel myself comfortable interacting in the workspaces.

with: total = every_course + every_course -------- output >>> 4 with just: total = every_course ----------- output >>>> 2 can someone explain me why?

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):
    return len(teachers)
my_teachers = {'Andrew Chalkley': ['jQuery Basics', 'Node.js Basics'],
 'Kenneth Love': ['Python Basics', 'Python Collections']}

def num_courses(courses):
    for every_course in courses.values():
        total = every_course + every_course
        return len(total)
print(num_courses(my_teachers))

1 Answer

Bryan Reed
Bryan Reed
11,747 Points
Bryan Reed
Bryan Reed
11,747 Points

Couple of things I see here.

First is that your return is inside your for loop which means it's only going to go through a single iteration before it's returned out.

Second is when you do every_course + every_course inside your for loop your basically doubling up the current value. Say for the first iteration of the loop every_course equaled ['jQuery Basics', 'Node.js Basics']. Then every_course + every_course would equal ['jQuery Basics', 'Node.js Basics', 'jQuery Basics', 'Node.js Basics'].

Maybe create the total variable before the loop and add the length of each value that is iterated to that total :)

    total = int()
    for current_courselist_in_iteration in courses.values():
        total += len(current_courselist_in_iteration)
    return total