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![Sebastian Knell](https://secure.gravatar.com/avatar/105208ed21837744e7e0c096d37f1180?s=96&d=https%3A%2F%2Fecs-static.teamtreehouse.com%2Fassets%2Fcontent%2Fdefault_avatar-445fbbabfc8dc9188fb5967fe43322ee0c3e0dd1e10f378bf8343784af5a13eb.webp&r=pg)
Sebastian Knell
927 PointsFor me it should be correct. Can anyone tell me why it is wrong?
Help please
# 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](https://uploads.teamtreehouse.com/production/profile-photos/969492/micro_tool_chess_set_2.jpg)
Steven Parker
230,688 PointsThe 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
927 PointsSebastian Knell
927 PointsOh, you're right. Thanks man.