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

Posted by Dean Pierrot
Dean Pierrot
18,403 Points

Having trouble accessing the courses of the teachers.

Create a function named most_courses that takes our good ol' teacher dictionary. most_courses should return the name of the teacher with the most courses. You might need to hold onto some sort of max count variable.

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_single_args):
    return len(a_single_args)

def num_courses(a_single_args):
    total = 0
    for value in a_single_args.values():
        for course in value:
            total += 1
    return total

def courses(a_single_dict):
    a_list = []
    for course in a_single_dict.values():
        a_list.extend(course)
    return a_list


def most_courses(a_single_dict):
    count = 0
    for teacher in a_single_dict:
        if len(teacher) > count:
            count += 1
        else:
            return count

1 Answer

Greg Kaleka
Greg Kaleka
39,021 Points
Greg Kaleka
Greg Kaleka
39,021 Points

Hi Dean,

There are a few things wrong here.

  1. You don't want to just arbitrarily add 1 to the count. Instead, if the length of the teacher's course list is longer than the current count, simply set the count to the length of the teacher's course list.
  2. You need to hold on to the teacher's name, since that's what your function should return.
  3. You're returning the count immediately if a given teacher isn't the longest - don't do that. Check every teacher, then return the longest; that's what the challenge is asking for. Remember to return the name, not the count.
  4. You're looping through keys in the dictionary, and checking their length. Instead, loop through keys and check the length of the values (which is the course list for that key/teacher). E.g. len(a_single_dict[teacher]) will give you the count of courses for that teacher. Make sense?

Give it another go, and then add a comment on this answer if you figure it out or if you have more questions.

Cheers :beers:

-Greg