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

Milos Radosavljevic
Milos Radosavljevic
9,081 Points

Im stuck here, i got the right answer, but it keep saying "Try again!"

Let's write some functions to explore set math a bit more. We're going to be using this COURSES dict in all of the examples. Don't change it, though! So, first, write a function named covers that accepts a single parameter, a set of topics. Have the function return a list of courses from COURSES where the supplied set and the course's value (also a set) overlap. For example, covers({"Python"}) would return ["Python Basics"].

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(x):
    courses_list = []
    for course in COURSES:
        if x.intersection(COURSES[course]):
        courses_list.append(course)
    return courses_list

1 Answer

Hi Milos,

You only have an indentation problem.

Your append statement should be indented 1 more level so that it's part of the if statement.