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Python Python Collections (2016, retired 2019) Sets Set Math

Posted by Kevin Li
Kevin Li
864 Points

I don't understand where I am wrong

I was working on a code challenge but I couldn't figure out how to get it to work. I think my solution is correct but according to the corrector it is wrong. It says that it didn't get the right output from "covers". Please help.

"Challenge Task 1 of 2 Let's write some functions to explore set math a bit more. We're going to be using this COURSES dict in all of the examples. Don't change it, though! So, first, write a function named covers that accepts a single parameter, a set of topics. Have the function return a list of courses from COURSES where the supplied set and the course's value (also a set) overlap. For example, covers({"Python"}) would return ["Python Basics"]."

sets.py 
COURSES = {
    "Python Basics": {"Python", "functions", "variables",
                      "booleans", "integers", "floats",
                      "arrays", "strings", "exceptions",
                      "conditions", "input", "loops"},
    "Java Basics": {"Java", "strings", "variables",
                    "input", "exceptions", "integers",
                    "booleans", "loops"},
    "PHP Basics": {"PHP", "variables", "conditions",
                   "integers", "floats", "strings",
                   "booleans", "HTML"},
    "Ruby Basics": {"Ruby", "strings", "floats",
                    "integers", "conditions",
                    "functions", "input"}
}

def covers(topics):
    listing = []
    for thing in COURSES.items():
        a, b = thing
        if topics.intersection(b) == topics:
            listing.append(a)
    return listing

3 Answers

Nafeez Quraishi
Nafeez Quraishi
12,416 Points

if topics.intersection(b) == topics:

I think, the Challenge is looking for overlaps including partial overlaps as well. So, we should easing the above condition as below to allow partial overlaps as well. 

if topics.intersection(b) == True: 
##OR 
if topics.intersection(b):
Kevin Li
Kevin Li
864 Points

Thank you! That really helped.

Jay Padzensky
Jay Padzensky
4,731 Points
Jay Padzensky
Jay Padzensky
4,731 Points

Hey Kevin,

I may recommend taking a peek at some of the previously created threads on the CC to perhaps get some insight into the task. Thanks, best of luck with it. Keep it up!

Hasan Ahmad
Hasan Ahmad
6,727 Points
Hasan Ahmad
Hasan Ahmad
6,727 Points

Can someone walk me through every line of code so I can fully understand what's going on? I'm struggling a bit to understand.