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

Why does my code for covers_all work in the workspace but not when I try to submit it for a challenge?

I'm try to figure out where I went wrong here. In the workspace, I get the correct answer but the challenge tells me that my answer was a "Bummer" and that I should "Try again!"

    "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(setss):
    lists = []
    for course, value in COURSES.items():
        if value & setss:
    return lists

def covers_all(topic):
  output = []
  for key, values in COURSES.items():
    if topic.issubset(values):
  return output

1 Answer

Chris Freeman
Chris Freeman
Treehouse Moderator 68,390 Points

In the function covers, the argument key is not defined. Perhaps you meant to use course instead.

Post back if you need more help. Good luck!!!