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

Gilbert Craig
Gilbert Craig
2,102 Points

Challenge passes but doesn't work in shell

This code gets "Congrats". When I run it in the shell with ({"strings"}) i get all four courses as expected. But , if I use ({"Ruby"}) expecting 'Ruby basics' as a result I get nothings .. Is my code wrong or the challenge wrong ?

    "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(arg):
    topic_match = []
    for keys, values in COURSES.items():
        if arg.intersection(values):
    return topic_match

1 Answer

Josh Keenan
Josh Keenan
19,652 Points
def covers(topics):
    courses = []
    for keys, values in COURSES.items():
        if topics.intersection(values):

    return courses

Here's my solution, you haven't accessed you argument at all, you have tried to access COURSES, change it to arg and I think you will be fine.