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

Posted by dylan hamm
dylan hamm
3,667 Points

please help with this. I don't know why it doesn't work

I have tried a loy of other things but I don't see why this doesn't work

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(set1):
    lyst = []
    for key, value in COURSES:
        if value & set1:
            lyst.append(key)
    return lyst

2 Answers

Chris Freeman
MOD
Chris Freeman
Treehouse Moderator 68,423 Points
Chris Freeman
Chris Freeman
Treehouse Moderator 68,423 Points

Trying to run the code locally revealed one syntax error.

ā€¢ to extract both the key and value from a dictionary you need the .items() method

for key, value in COURSES.items()
Mduduzi Frederick Dube
Mduduzi Frederick Dube
8,886 Points
Mduduzi Frederick Dube
Mduduzi Frederick Dube
8,886 Points

Try actually doing something to lyst for every val that is in the intesection of set1 and the value in COURSES, which happens to be a set too.

for key, value in COURSES.items():
    for val in set1.intersection(value):
        lyst.append(key)

return lyst