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Python Python Collections (Retired) Dictionaries Teacher Stats

Einars Vilnis
Einars Vilnis
8,050 Points

Hi. fellow treehouse mates. i get bummer in the last task about courses. that says You returned 5 should be 18. why

i het all the values printed what is wrong with my answer?

teachers.py
# The dictionary will be something like:
# {'Jason Seifer': ['Ruby Foundations', 'Ruby on Rails Forms', 'Technology Foundations'],
#  'Kenneth Love': ['Python Basics', 'Python Collections']}
#
# Often, it's a good idea to hold onto a max_count variable.
# Update it when you find a teacher with more classes than
# the current count. Better hold onto the teacher name somewhere
# too!
#
# Your code goes below here.
def most_classes(teachers):
  max_count = 0
  max_teacher = ''
  for key in teachers:
    class_count = len(teachers[key])
    if class_count > max_count:
      max_teacher = key                   #You have to reassign max_count to have the current
      max_count = class_count             #class count here
  return max_teacher

def num_teachers(teachers):
  count = 0
  for keys in teachers:
    count += 1
  return count

def stats(teachers):
  teacher_list = []
  for keys in teachers:
    teacher = [keys, len(teachers[keys])]
    teacher_list.append(teacher)
  return teacher_list

def courses(teachers):
  course_list = []
  for values in teachers.values():
    course_list.append(values)
  return course_list

1 Answer

Hi Einars,

teachers.values() returns a list. When appending a list to another list, you get a list of lists [[], [], []]. This challenge is expecting just one list. Instead of appending, there is an operator you can use to Combine Lists for the desired result.