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When I use print, instead of return - I can see that my code isn't just creating a single list, with a single length, it is creating a list for each teacher in the course

So calculating the length of the list results in multiple calculations- one for each list.

I guess it is because it is running the code for each key, rather than in total, but I don't know why.

Any help would be appreciated! Thank you!

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(teachers):

print(teachers)
word_count =0
for teacher in teachers:
word_count +=1
return word_count

def num_courses(teachers):

all = []
for value in teachers.values():
all.extend(value)
return len(all)

Hello Jen, You be able to pass the challenge by adding (+=) instead.

def num_teachers(teachers):
print(teachers)
word_count =0
for teacher in teachers:
word_count +=1
return word_count

def num_courses(teachers):
courses = []
for course in teachers.values():
courses += course
return len(courses)