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

yannis sousanis
yannis sousanis
7,199 Points

need help

when I run this program i get 2 list in one [['jQuery Basics', 'Node.js Basics'], ['Python Basics', 'Python Collections']] do I have to unpack this to return a single list?

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(a):
    return len(a)
def num_courses(dic):
    number = 0
    for v in dic.values():
        number += len(v)
    return number
def courses(dic):
    course_list = []
    for v in dic.values():
        course_list.append(v)
    return course_list    

1 Answer

Jordan Hoover
seal-mask
.a{fill-rule:evenodd;}techdegree seal-36
Jordan Hoover
Python Web Development Techdegree Graduate 59,268 Points

Just loop one more time, or combine it with a comprehension.

for teacher_courses in dic.values():
    for course in teacher_courses:
        course_list.append(course)