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

Help with sets

Hello I'm not all that great with coding and had to find help from a previous post on these forums to get step 1 of this challenge correct. I am stuck on step 2 in which I am suppose to list everything covered in COURSES. Going off the example I figured what I did was along the right line of thinking, but I guess not. Can anyone help me out here?

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(param1):
    r_list = []
    for k,v in COURSES.items():
        if param1.union(v):
            r_list.append(k)
    return r_list

def covers_all(total):
    all_list = []
    all_list.append(COURSES({"integers", "strings"}))
    return all_list

1 Answer

Chris Freeman
MOD
Chris Freeman
Treehouse Moderator 68,426 Points

I believe the challenge checker has changed since you originally posted your question.

In covers, the method intersection should be used instead of union.

In covers_all, the process is similar to covers except a more precise subset check is needed. Use the method issubset instead of the intersection used in `covers.

Good luck!!