TypeError: string indices must be integers, not str // working with dict

Question

I am trying to define a procedure, involved(courses, person), that takes as input a courses structure and a person and returns a Dictionary that describes all t

Answer 1

Actually I think that more general approach to loop through dictionary is to use iteritems():

# get tuples of term, courses
for term, term_courses in courses.iteritems():
    # get tuples of course number, info
    for course, info in term_courses.iteritems():
        # loop through info
        for k, v in info.iteritems():
            print k, v

output:

assistant Peter C.
prereq cs101
...
name Programming a Robotic Car
teacher Sebastian

Or, as Matthias mentioned in comments, if you don't need keys, you can just use itervalues():

for term_courses in courses.itervalues():
    for info in term_courses.itervalues():
        for k, v in info.iteritems():
            print k, v