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

Posted by priyanka shukla
priyanka shukla
3,051 Points

why its showing didnt got right output

i tried and it was correctly working in idle but not working here why

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):
    list_courses=[]
    for course in COURSES:
        if topics in COURSES[course]:
            list_courses.append(course)

    return list_courses

1 Answer

Alexander Davison
Alexander Davison
65,469 Points
Alexander Davison
Alexander Davison
65,469 Points

in checks if a value is within an iterable. But COURSES[course] is a one-dimensional set, which could not possibly contain another set.

Try using the method intersect instead.

If you need more hints, feel free to ask.

priyanka shukla
priyanka shukla
3,051 Points

hi alexander can you just show give an example where it won't run properly just to understand it more cleary beacuse i tried add a set in dictionary in keys but it does'nt work so if can't add a set then i should worry about about another set. Thnks again!! sry i ask very silly doubts but this one is really troubling me

Alexander Davison
Alexander Davison
65,469 Points

For example,

If COURSES[course] were {"Python", "functions", "variables", "booleans", "integers", "floats", "arrays", "strings", "exceptions", "conditions", "input", "loops"}, and you are checking with the topics being {"HTML", "strings"}, course should be included in the result because of the "string" overlap.