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Python Functional Python The Lambda Lambada Recursion

Andy McDonald
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Andy McDonald
Python Development Techdegree Graduate 13,801 Points
Posted by Andy McDonald
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Andy McDonald
Python Development Techdegree Graduate 13,801 Points

Isnt there a way to index a dictionary by passing the keyword?

I vaguely remember being able to index a dictionary by passing the string for the keyword inside brackets. Did I imagine this?

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 prereqs(data, pres=None):
    pres = pres or set()
    for course in data:
        for pre in course['prereqs']:
            pres.add(pre.title)

1 Answer

jb30
jb30
44,806 Points

Yes, courses["prereqs"] is the list of sets

                     [{'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': []}]

Try changing pres.add(pre.title) to pres.add(pre["title"]).