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

Duyen Huynh Ngoc Phuong
Duyen Huynh Ngoc Phuong
3,494 Points

Can you help me to figure what is wrong with my code. I cannot pass the challenge.

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.

def covers_all(single_set):
    new_list = []
    for key, value in COURSES.items():
        if (single_set & value)==single_set:
             new_list.append(key)
    return new_list
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 B-asics": {"PHP", "variables", "conditions",
                   "integers", "floats", "strings",
                   "booleans", "HTML"},
    "Ruby Basics": {"Ruby", "strings", "floats",
                    "integers", "conditions",
                    "functions", "input"}
}

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

def covers(arg):
    hold = []
    for key, value in COURSES.items():
        if value & arg:
            hold.append(key)
    return hold

2 Answers

Don Newcomb
Don Newcomb
4,755 Points

I looked at your problem and tried to pass it, but it would not pass do to the "-" you placed here "PHP B-asics": just change that to "PHP Basics": and it should work fine. that was the only thing I found wrong :)

Steven Parker
Steven Parker
229,005 Points

Good catch! :+1: I didn't even think that the provided data might have been changed. I only pasted in the code portion.

Steven Parker
Steven Parker
229,005 Points

You solution looks good. So I pasted it directly into the challenge and it passed. Does it not pass for you?

Duyen Huynh Ngoc Phuong
Duyen Huynh Ngoc Phuong
3,494 Points

Yes, I tried it many times, the first challenge passed, but the second one did not.

Duyen Huynh Ngoc Phuong
Duyen Huynh Ngoc Phuong
3,494 Points

I have tried to log out of my account and logged in again. Luckily the solution is passed this time. Thank you

Steven Parker
Steven Parker
229,005 Points

Don found it .. a stray character somehow got inserted into the supplied data.