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return a list of courses from COURSES where the supplied set and the course's value (also a set) overlap.
I've tested this several different ways and it seems to work, but it fails the challenge. Not looking for a solution, just a clue as to what I am missing.
def covers(topics): # topics = type set list_of_courses =  # the key for topics that overlap # compare topics w/ dct value # if topics and value overlap # append key to list_of_courses for key, value in COURSES.items(): if value.intersection(set_of_topics): list_of_courses.append(key) return list_of_courses
It's hard to give a hint on this without giving away the solution because you're so close.
Take a look at the names of your variables.
topics is the parameter to your function. Where are you using that in your code?