Task 2/2: How do I find the right intersection?

I am trying to use the operand & to find where key and value overlap.

I am not sure how I find the right way to return a set, the right set.

Task descriptions are in the bottom of this post.

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(param):
    returnable = []
    for course in COURSES:
        if COURSES[course] & param:
            returnable.append(course)
    return returnable

def covers_all(a_set):
    returnable = []
    for course in COURSES:
        for parameters in course:
            if course[a_set] & course:
                returnable.append(course)
    return returnable

Task 1:

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"].

Task 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 exclude because they don't include both of those topics.