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

Venkat SOMALARAJU
Venkat SOMALARAJU
2,448 Points
Posted by Venkat SOMALARAJU
Venkat SOMALARAJU
2,448 Points

COURSES Practicing tasks on sets.

Can someone tell me what's incorrect here?

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"].

print(covers({"strings","floats"})) --> Input

['Python Basics', 'Ruby Basics', 'PHP Basics'] -->Result

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(param1):
    set1 = {}
    set1 = param1
    return_val= []
    i=0
    for key,value in COURSES.items():
        set2 = value & set1
        difference = set1 - set2
        if len(difference) ==0 :
            return_val.insert(i, key)
            i += 1
        else:
            continue
    return return_val

1 Answer

Chris Freeman
MOD
Chris Freeman
Treehouse Moderator 68,441 Points
Chris Freeman
Chris Freeman
Treehouse Moderator 68,441 Points

There seems to be more going on than necessary.

The if need only check if set2 is non-empty then simply append the course (key) to the results list:

        if set2:
            return_val.append(key)