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

Posted by jalil damian
jalil damian
1,452 Points

Great work! OK, you're doing great so I'll keep increasing the difficulty. For this step, make an

can some one help challenge 3

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):
    course = 0
    for teacher in teachers:
        course += 1
    return course

def num_courses(a_dict):
    total = 0
    for key, value in a_dict.items():
        total += len(value)
    return total

3 Answers

Alexandra Barnett
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.a{fill-rule:evenodd;}techdegree seal-36
Alexandra Barnett
Front End Web Development Techdegree Graduate 46,473 Points
Alexandra Barnett
.a{fill-rule:evenodd;}techdegree seal-36
Alexandra Barnett
Front End Web Development Techdegree Graduate 46,473 Points

Hi Jalil! Great work so far!

You need to make a function and create an empty list (master list) for all the courses that will be returned at the end. The tricky bit is the for loop(s). You need to loop over the dictionary (like you did in the previous task) but, the list of courses from the value of the key/value pair cannot be added to your master list because you will have lists inside of a list. This means you need to loop over the list of courses for each teacher and then add each course individually into the master list. It results in having a for loop nested inside of another for loop like so:

def courses(a_dict):
    total_courses = []
    for key, value in a_dict.items():
        for course in value:
            total_courses.append(course)

    return total_courses

That was a bit long winded but I hope some of that made some sense - let me know if you have any questions! :)

jalil damian
jalil damian
1,452 Points

hey can you help me when i need help

jalil damian
jalil damian
1,452 Points

ok i follow you on github.com

jalil damian
jalil damian
1,452 Points

hey how do i make a dict to return name

jalil damian
jalil damian
1,452 Points

hey i need help

jalil damian
jalil damian
1,452 Points
jalil damian
jalil damian
1,452 Points

thank you rely again

jalil damian
jalil damian
1,452 Points
jalil damian
jalil damian
1,452 Points

hey