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Python Python Collections (Retired) Dictionaries Teacher Stats

most_classes challenge - Incorrect answer, even though code is correct

My code for most_classes challenge attached.

When i run this with example dict in my PC it works and returns Jason Seifer. However, on checking in to treehouse it says it's giving Kenneth Love. Any ideas?

Example dict: {'Jason Seifer': ['Ruby Foundations', 'Ruby on Rails Forms', 'Technology Foundations'], 'Kenneth Love': ['Python Basics', 'Python Collections']}

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(teach_dict):
  count = 0
  teacher = ''
  for teach in teach_dict:
    if len(teach_dict[teach]) > count:
      count = len(teach_dict[teach])
      teacher = teach
  return teach

2 Answers

Chris Freeman
MOD
Chris Freeman
Treehouse Moderator 68,166 Points

Your code, as written, returns "teach". This will always be the last teacher in the iterated list. With dictionaries, you don't know the order in which the items will be iterated. Replace "teach"with "teacher":

    return teacher

If the last teacher happens to be the one with the maximum count here code will return the correct answer, but for the wrong reason.

Thanks a lot, I totally missed it.