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

Posted by Jeffrey Shalagan
Jeffrey Shalagan
5,078 Points

Set Math Python

Hi there,

I saw on another post that using the intersection method would allow me to pass task 1, though I just wanted to ask why my method isn't working? Thanks!

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(s):
    li = []

    for course, topic in COURSES.items():
        if topic in s:
            li.append(course)

    return li
AJ Salmon
AJ Salmon
5,675 Points
AJ Salmon
AJ Salmon
5,675 Points

Hello Jeffery, The problem here is your syntax. 'in' is not the correct keyword to use when comparing sets when using the intersection method. Remember, .intersection() and '&' perform the same operation. Simply replacing 'in' with '&' passes the challenge!

def covers(s):
    li = []

    for course, topic in COURSES.items():
        if topic & s:
            li.append(course)

    return li