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Python Python Collections (2016, retired 2019) Dictionaries Teacher Stats

Abdullah Jassim
Abdullah Jassim
4,551 Points
Posted by Abdullah Jassim
Abdullah Jassim
4,551 Points

I am not sure why the answer is wrong

def courses(arg):
    single_list = []
    for course in arg.values():
        single_list.append(course)
teachers.py 
def num_teachers(arg):
    teachers = int(len(arg))
    return teachers

def num_courses(arg):
    count_courses = 0
    for values in arg.values():
        for number in values:
            count_courses += 1
    return count_courses

def courses(arg):
    single_list = []
    for course in arg.values():
        single_list.append(course)


# The dictionary will look something like:
# {'Andrew Chalkley': ['jQuery Basics', 'Node.js Basics'],
#  'Kenneth Love': ['Python Basics', 'Python Collections']}
#
# Each key will be a Teacher and the value will be a list of courses.
#
# Your code goes below here.

2 Answers

Unsubscribed User
Unsubscribed User
7,263 Points

Hello Abdullah, you have the right idea but when you iterate through the values the item you get is a list with courses. You have to iterate in this list again and then append courses in your list.

something like this: 

single_list = []
for list_of_courses in args.values():
    for course in list_of_courses:
        single_list.append(course)

or if you don't want to make another for-loop you can use list comprehensions like this:

single_list = []
for list_of_courses in args.values():
    single_list.extend([course for course in list_of_courses])
Philip Schultz
Philip Schultz
11,437 Points
Philip Schultz
Philip Schultz
11,437 Points

Hello Abdullah, Remember that you need to use a for loop to access each value, but since you values are lists you have to loop through that also. 

def courses(sing_arg):
    list_courses = []
    for values in sing_arg.values():
        for courses in values:
            list_courses.append(courses)
    return list_courses