How can I proceed with the code below? Writing a function to search a set of values within a dict and return their key

Question

Thanks in advance!!!
```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({setoftopics}):
    courselist = {}
    for topics in setoftopics:
            if topics in COURSES.values():
                courselist.add(COURSES.keys())
    finallist = list(courselist)
    return final_list
```

Stuart Wright · Accepted Answer

This challenge is easier to solve by looping over the dictionary and checking to see if any of the courses are in the set, rather than the other way around.
The problem with your method is that when you write:
python
if topics in COURSES.values():
    course_list.add(COURSES.keys())

You are checking if the topic belongs anywhere in the dictionary, and you  then add all the keys. When you should only be adding the key that the topic was found in.
Here is my solution using method I've described above:
python
def covers(set_of_topics):
    course_list = []
    for course, topics in COURSES.items():
        if set_of_topics.intersection(topics):
            course_list.append(course)
    return course_list

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Deniz Kahriman

Deniz Kahriman

How can I proceed with the code below? Writing a function to search a set of values within a dict and return their key

1 Answer

Stuart Wright

Stuart Wright

Deniz Kahriman

Deniz Kahriman