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

Daniel Bourke
Daniel Bourke
3,870 Points
Posted by Daniel Bourke
Daniel Bourke
3,870 Points

Unable to correctly count number of values in a dictionary

For the most_courses function. I'm trying to return the key (teachers name) with the most number of values. I've been stuck on this problem for a while but can't seem to figure it out.

My logic is:

  • Loop through the dictionary
  • Create a variable (maxcount) that keeps track of the key with the highest number of values
  • Loop through the dictionary again
  • Compare maxcount to the values in the dictionary a second time
  • If there's a match, return the key

Any help would be greatly appreciated!

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_users):
    return len(dict_users.keys())

def num_courses(dict_users):
    course_count = []
    for item in dict_users.values():
        course_count += item
    return len(course_count)

def courses(dict_users):
    all_courses = []
    for x in dict_users.values():
        all_courses.extend(x)
    return all_courses

def most_courses(dict_users):
    maxcount = max(len(v) for v in dict_users.values())
    for k, v in dict_users.items():
        if len(v) == maxcount:
        return k
Daniel Bourke
Daniel Bourke
3,870 Points
Daniel Bourke
Daniel Bourke
3,870 Points

I think I found the answer! My return k (in most_courses) wasn't indented correctly.

If anyone has any different ways of solving this, I'd still love to see them, please.

Kurt L
Kurt L
22,856 Points
Kurt L
Kurt L
22,856 Points

I think you just need to indent the "return k" line once more.