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Todd Costa
3,380 PointsTask 5/5 - 'NoneType' is not iterable but works correctly in workspaces
Hey guys, title really says it all. I'd like to understand why it doesn't work. Thanks in advance!
# 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):
return len(teachers.keys())
def num_courses(courses):
count = 0
for course in courses.values():
for item in course:
count += 1
return count
def courses(courses):
new_list = []
for course in courses.values():
for item in course:
new_list.append(item)
return new_list
def most_courses(arg):
max_count = 0
teachers = " "
for teacher, listOfCourses in arg.items():
if len(listOfCourses) > (max_count):
max_count = len(listOfCourses)
teachers = teacher
return teachers
def stats(a_dict):
new_list = []
for teacher in a_dict.keys():
num_courses = len(a_dict[teacher])
new_list.append([teacher, num_courses])
print(new_list)
3 Answers

Brendan Chamberlain
2,753 PointsYour code is fine you're just printing your new_list variable instead of returning it.

Todd Costa
3,380 PointsThank you! I'm happy its a silly mistake at least.

Jose Lopez
4,615 PointsI am very confused. Why are you using the len() function? I keep getting an error when I use it