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

drstrangequark
drstrangequark
8,273 Points
Posted by drstrangequark
drstrangequark
8,273 Points

How do I get a specific key in a dictionary?

I am trying to get the key of a dictionary if the value is equal to a maxcount variable. However, when I try to print it out, I get EVERY key instead of just the one I want. This question is specifically related to the most_courses function. Any advice on how to solve this?

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.keys()))

def num_courses(teachers):
    courses = []
    for value in teachers.values():
        courses.extend(value)
    return(len(courses))

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

def most_courses(teachers):
    maxcount = max(len(value) for value in teachers.values())
    for item in teachers.items():
        if teachers.values() == maxcount:
            print(teachers.keys())

1 Answer

Adriano Junior
Adriano Junior
5,065 Points
Adriano Junior
Adriano Junior
5,065 Points

Hey, @drstrangequark. I feel your pain, this code challenge can be tricky.

From what I've seen in your code, you're trying to do too much just in the definition of the max_count variable. You're also looping through the wrong values. You don't want to loop through teachers.items(), but yes teachers.keys(). And also you're not returning the intended value, you're printing it. It does look like it, but they are different. Here's my suggestion for your code:

Define "teachers" if you want to test it out.

teachers = {} #This is just in case you want to test it out in workspaces first, or on your selected IDE.

def most_courses(teachers): max_count = 0 winner = "" for x in teachers.keys(): count = len(teachers[x]) if count >= max_count: max_count = count winner = x

print(winner) #This is just in case you want to test it out in workspaces first, or on your selected IDE.
return winner

most_courses(teachers) #This is just in case you want to test it out in workspaces first, or on your selected IDE.

I hope this was helpful.

Cheers!