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

Alejandro Byrne
Alejandro Byrne
2,562 Points

Why can't the challenge find my function?

Hi, the error I get when I put my code in is "Couldn't find 'covers'!". Why? And, if you found a way to make that work, could you help me with the rest of the function, I have a few issues...

def covers(course):
    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"}
    output = []
    if course in COURSES["Python Basics"].intersection(COURSES["Java Basics"]):
        output.append("Java Basics")
    if course in COURSES["Python Basics"].intersection(COURSES["PHP Basics"]):
        output.append("PHP Basics")
    if course in COURSES["Python Basics"].intersection(COURSES["Ruby Basics"]):
        output.append("Ruby Basics")
    if "Ruby Basics" or "Java Basics" or "PHP Basics" in output:
        output.append("Python Basics")
    return output
Tri Pham
Tri Pham
18,671 Points

yeah the error messages aren't too helpful and theres really no way to figure out what you did wrong. thats why I suggest you use an online ide like this so you can print() out some stuff and see what you are getting.

First, you should probably leave COURSES outside of the function.

More importantly Second, your expected input is not a course but a Set of topics.

1 Answer

Chris Freeman
Chris Freeman
Treehouse Moderator 68,423 Points

The challenge checker can't find the function covers due to the syntax error in the last if statement. The or must be complete statements, such as:

if "Ruby Basics" in output or "Java Basics"  in output or "PHP Basics" in output:

With this syntax correct it will run but not provide the correct results. Try running it locally so that you can test the function output.