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

Kade Carlson
Kade Carlson
5,928 Points

Not sure what this error message means

Ran my code and got this error message, Bummer! Couldn't find covers.

Not sure what it means. Can someone help me please?

    "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(topic):
    courses_on_topic = []
    for course_name in set(COURSES.keys()):
        if len(topic.intersection(COURSES[course_name])) > 0:
    return courses_on_topic

def covers_all(course):
    all_topics = []
    for item in set(COURSES.keys()):
        if len(coures.union(COURSES[item])) > 0:
    return all_topics

1 Answer

Steven Parker
Steven Parker
229,004 Points

Yes, that message isn't very helpful.

If you introduce an error that invalidates the whole program, the checker can misinterpret the problem while it re-checks the earlier task.

What's actually causing the problem is on the third line of covers_all where you wrote "coures" instead of "course". You still have some logic to work on, but hopefully this will get you back on track.