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Python Functional Python The Lambda Lambada Recursion

Prerequisite Challenge - Code works in PyCharm but give an error in code challenge

The following code works in PyCharm but give the error "Bummer: Can't find preregs" in the code challenge

courses.py
courses = {'count': 2,
           'title': 'Django Basics',
           'prereqs': [{'count': 3,
                     'title': 'Object-Oriented Python',
                     'prereqs': [{'count': 1,
                               'title': 'Python Collections',
                               'prereqs': [{'count':0,
                                         'title': 'Python Basics',
                                         'prereqs': []}]},
                              {'count': 0,
                               'title': 'Python Basics',
                               'prereqs': []},
                              {'count': 0,
                               'title': 'Setting Up a Local Python Environment',
                               'prereqs': []}]},
                     {'count': 0,
                      'title': 'Flask Basics',
                      'prereqs': []}]}

def preregs(data, pres=None):
    pres = pres or set()
    for prereg in data['prereqs']:
        pres.add(prereg['title'])
        preregs(prereg, pres=pres)
    return pres

2 Answers

Mel Rumsey
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STAFF
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Mel Rumsey
Treehouse Staff

Heya Akio Ito, your code looks great! :D

There are just a couple of typos that are causing your code to fail for the challenge. Right now you have 'prereg' written with a G rather than prereq with a Q. Once you correct those 'g's to 'q's that should solve the challenge. Nice job!

Haha! Of course, a typo error. Thank you so much!