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Python Python Collections (Retired) Dictionaries Teacher Stats

21,570 Points

Write a function named courses that takes the dictionary of teachers.

Currently getting "Bummer! You returned 5 courses, should have returned 18."

Could someone please explain why this is?


# 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_dict):
  max_count = 0
  busiest_teacher = ''
  for teacher, classes in teachers_dict.items():
    if len(classes) > max_count:
      max_count = len(classes)
      busiest_teacher = teacher
  return busiest_teacher

def num_teachers(teachers_dict):
  teacher_count = 0
  for teacher in teachers_dict:
    teacher_count += 1
  return teacher_count

def stats(teachers_dict):
  newList = []
  for teacher in teachers_dict:
  return newList

def courses(teachers_dict):
  courseList = []
  for classes in teachers_dict.values():
  return courseList

2 Answers

Chris Freeman
Chris Freeman
Treehouse Moderator 68,423 Points

Your courses function needs some help:

def courses(teachers_dict):
    courseList = []
    for classes in teachers_dict.values():  # gets a **list** contain teachers courses.
        # extends courseList the contents of your [] list. which is a single item: the teachers course list
        courseList.extend([classes])  # <-- fix by removing "[" and "]" from around `classes`
    return courseList

Without the change your adding lists to courseList. 5 teachers, 5 lists. With the change your code extends courseList with the contents of the list classes: Now all 18 courses are at the same level in courseList

Aside: course_list would be a more Pythonic variable name. Camel case isn't a python thing except for class names.

21,570 Points

Chris, thank you very much!