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

Abdulkadir Kollere
Abdulkadir Kollere
1,723 Points

Need Hint

I know that the intersection method is to be used in this challenge. But I don't know how to select the KEY of the value in the dictionary. Any hint is appreciated.

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 (elem):
    if elem & courses == True:

1 Answer

Steven Parker
Steven Parker
229,980 Points

There are various ways to get dictionary keys.

If you just want a collection of only keys, you can apply the .keys() method to the dictionary.

But if you're going to create a loop where you will do something with each key individually, the key is normally the thing you will iterate with:

for key in COURSES:

Inside the loop, the key can then be used as an index to the get associated values.