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

I'm stuck here i don't know where I'm going wrong. (Python)

Challenge Task 2 of 2 Great work!

OK, let's create something a bit more refined. Create a new function named covers_all that takes a single set as an argument. Return the names of all of the courses, in a list, where all of the topics in the supplied set are covered.

For example, covers_all({"conditions", "input"}) would return ["Python Basics", "Ruby Basics"]. Java Basics and PHP Basics would be excluded because they don't include both of those topics.

Bummer: Try again!
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(topic): courses_list = [] for name, topics in COURSES.items(): if topic & topics: courses_list.append(name) return courses_list ā€‹ def covers_all(arg): courses_list = [] for name, topics in COURSES.items(): if topic & topics: return courses_list ā€‹

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(topic):
    courses_list = []
    for name, topics in COURSES.items():
        if topic & topics:
            courses_list.append(name)
    return courses_list

def covers_all(arg):
    courses_list = []
    for name, topics in COURSES.items():
        if topic & topics:
    return courses_list

1 Answer

Steven Parker
Steven Parker
229,644 Points

Here's a few hints:

  • it looks like there may be a line missing between the last "if" and the "return"
  • the "if" refers to "topic", but that name is not defined in that function
  • you might need a slightly different test to determine complete coverage (vs. partial in the previous task)

Thanks Parker i got it

Steven Parker
Steven Parker
229,644 Points

Morningstar Ndlovu ā€” Glad to help. You can mark a question solved by choosing a "best answer".
And happy coding!