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

return names of all courses

I'm trying to return names of all courses in task 2, but my codes keeps crashing

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,sets in COURSES.items():
        if topics.intersection(sets):
            course_list.append(course)
    return course_list        

def covers_all(single_set):
    all_course=[]
    single_set = set(single_set)
    for topics,sets in covers_all.items():
        all_course.append(topics)
    return all_course    

2 Answers

Henrik Christensen
seal-mask
.a{fill-rule:evenodd;}techdegree
Henrik Christensen
Python Web Development Techdegree Student 38,322 Points

I would do something like this

def covers_all(single_set):
    items = list(single_set)  # turning the given set into a list
    result = []  # list to return
    # looping through the COURSES dict
    for x, y in COURSES.items():
        # checking if both items from the 'single_set are in the sets in COURSES
        if items[0] in y and items[1] in y:
            result.append(x)
    return result

That's the function name