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

using subset and still can't figure out this challenge.

I am using subset to solve this problem and now I just don't think I properly understand this problem.

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(topics): 
    course_list=[]
    for course in COURSES: 
        if topics & COURSES[course]:
            course_list.append(course)
    return course_list

def covers_all(singleset): 
    coverall=[]
    for keys, values in COURSES.items(): 
        if singleset.subset(values): 
            coverall.append(keys)
    return coverall

1 Answer

I read the function incorrectly: it's .issubset() not .subset().