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Python

Posted by Peter Gess
Peter Gess
16,553 Points

Why isn't this passing? What am I missing?

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

def covers_all(topics):
    result = [] 
    for key, value in COURSES.items():
        if topics & COURSES.keys() == topics:
            result.append(key)
    return result
Kyle Hartigan
Kyle Hartigan
16,967 Points

Hi Peter,

It doesn't make much sense to be checking the keys and not the values in your if check. You are looking to see if the value already exists not the key.

2 Answers

Carlos Marin
Carlos Marin
8,009 Points
Carlos Marin
Carlos Marin
8,009 Points

The problem is in the If section.

if topics & COURSES.keys() == topics:

When you input {"conditions", "input"} as a parameter.
type(topics) = 'set' type(COURSES.keys()) = 'dict_keys' in order to get .intersection() to work; both operands must both equal to sets.

What is needed? Access the set of the dictionary (COURSES). and compare it to the similarities of the values and the set of the dictionary(COURSES). {hint: if x[0] = y & x[0]}: you can also use the set() method to convert an iterable. Hope this helps, Carlos A. Marin

Peter Gess
Peter Gess
16,553 Points
Peter Gess
Peter Gess
16,553 Points

Thanks @kylehartigan. I miss read the question. I now updated to just the values and still not passing. Any idea?

def covers_all(topics):
    result = [] 
    for key, value in COURSES.items():
        if topics & COURSES.value():
            result.append(value)
    return result