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Anders Axelsen
3,471 PointsTask 3 of 5: How do I prevent my code from returning a list of a list?
I get this error: Bummer! Did you return a list of lists? I need just a single list.
- Note for developers: It can be hard to research debugging, when both order of tasks and function names have changed over time.
# The dictionary will look something like:
#
# Each key will be a Teacher and the value will be a list of courses.
#
# Your code goes below here.
def num_courses(dict1):
count = 0
for i in dict1:
list1 = dict1[i]
for i in list1:
count += 1
return count
def num_teachers(teachers_dict):
return len(teachers_dict)
def courses(dictus):
allCourses = []
for courses in dictus.values():
for course in courses:
allCourses.extend(dictus.values())
return allCourses
2 Answers
Steve Hunter
57,712 PointsHi Anders,
I think the second for loop is causing the problem here. I'll check now, but I think your code is fine if you just omit that loop.
[EDIT] The second loop is unnecessary but you're appending the wrong thing to your list. dictus.values() is a list. You want to extend the allCourses list with courses:
def courses(dictus):
allCourses = []
for courses in dictus.values():
allCourses.extend(courses)
return allCourses
Steve.
Anders Axelsen
3,471 PointsHi Steve!
Thank you - what a relief. It works with exending the allCourses by the means of (courses).
Kind regards, Anders.
Steve Hunter
57,712 PointsNo problem! 
