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

Posted by Sebastian Knell
Sebastian Knell
927 Points

For me it should be correct. Can anyone tell me why it is wrong?

Help please

teachers.py 
# 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.

def num_teachers(dict):
    teachers = dict.keys()
    return len(teachers)

def num_courses(dict):
    courses = dict.values()
    for sublist in courses:
        for course in sublist:
            flat_list = []
            flat_list.append(course)

    return len(flat_list)

1 Answer

Steven Parker
Steven Parker
231,236 Points
Steven Parker
Steven Parker
231,236 Points

The code shown above sets "flat_list" to be empty for each course before adding that course to it, so it will never contain more than one item.

Perhaps you intended to do this initialization only once at the beginning of the function?

Sebastian Knell
Sebastian Knell
927 Points

Oh, you're right. Thanks man.