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

Bummer! Try again!

Please tell me what's wrong with my code?

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(arg):
    list = [ ]
    for key,value in COURSES.items():
        if value & arg:
            list.append(key)
    return list

def covers_all(arg):
    list = [ ]
    for key, value in COURSES.item():
        if arg.issubset(value):
            list.append(key)
    return list

1 Answer

Oszkár Fehér
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Oszkár Fehér
Treehouse Project Reviewer

Hi Chen. Your functions are working well and they pass the quiz it's just a typo in the second function: In this line

    for key, value in COURSES.item():

it's missing an "s" from the

    COURSES.items():

Also for best practice try to not leave empty space in empty list variables

list = [ ]

instead

list = []

I hope this helps. Happy coding

Thank U.