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Python Functional Python The Lambda Lambada Recursion

Which method should i use to get the child's title?

Should it be itemgetter?

1 Answer

Not sure I understand your question. What the challenge wants you to do it finish the function. Here's one way to do that:

def prereqs(data, pres=None):
    pres = pres or set()
    # for each prereq in this courses' prereqs...
    for prereq in data['prereqs']:
        # add title of this prereq course, then...
        pres.add(prereq['title'])
        # use recursive call to find further prerequisites of this
        # course, if any
        prereqs(prereq, pres)
    # return current 
    return pres

This solution comes from Chris Freeman: https://teamtreehouse.com/community/functional-python-recursion

His is better than the one I came up with, plus it has comments that should be helpful.

Thank you for help. It's really easier than i thought.