Welcome to the Treehouse Community

The Treehouse Community is a meeting place for developers, designers, and programmers of all backgrounds and skill levels to get support. Collaborate here on code errors or bugs that you need feedback on, or asking for an extra set of eyes on your latest project. Join thousands of Treehouse students and alumni in the community today. (Note: Only Treehouse students can comment or ask questions, but non-students are welcome to browse our conversations.)

Looking to learn something new?

Treehouse offers a seven day free trial for new students. Get access to thousands of hours of content and a supportive community. Start your free trial today.

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

victor escarcega
victor escarcega
15,083 Points

i am having a hard time converting this into a list of courses. list() and return do not give correct output

i am having a hard time converting this into a list of courses. list() and return do not give correct output

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):
    for key, value in COURSES.items():
        if topics in COURSES[key]:
            print (key)

1 Answer

Steven Parker
Steven Parker
220,696 Points

Remember that "topics" is a set, so it's not likely to be found (in it's entirety) as a member of the set of topics associated with one of the courses.

What you're looking for is any overlap (any items in common) between the set passed in as the argument and one associated with a course. One of the "set math" operators could be handy here.

victor escarcega
victor escarcega
15,083 Points

thanks for the tip, this is how i got the right answer! def covers(topics): lst = [] for key, value in COURSES.items(): if topics & COURSES[key]: lst.append(key) return lst